First work out the area of the triangle. Multiply the base by the height and divide by two, (5 × 4)/2 = 10. The area of the triangular cross-section is 10 mm². Image caption, Next …A triangular prism’s surface area is also known as its total surface area. It is equal to the sum of the areas of all its faces. Knowing the base, length and height of a triangular prism is all that is required to calculate its surface area. The total surface area of a triangular prism is equal to the sum of twice the base area and thrice the ...The formula for the surface area of a triangular prism is SA = bh + (s1 + s2 + s3)H. In this formula, “b” is the triangle base, “h” is the triangle height, “s1,” “s2” and “s3” are ...The surface area of an isosceles triangular prism is defined as the total area of all the faces of an isosceles triangular prism. An isosceles triangular prism is a polyhedron with polygons as its faces. It has 6 vertices, 5 faces, and 9 edges. Out of the 5 faces, isosceles triangles form the two parts at the base facing each other and rectangles form the vertical …Intertrigo is inflammation of the skin folds. It tends to occur in warm, moist areas of the body where two skin surfaces rub or press against each other. Such areas are called inte...To calculate the lateral surface area triangular prism, the sides B, C and D are need to be added to calculate the area. Option A. is correct. The triangular prism is what? a triangle-shaped prism "a polyhedron with two triangular bases, three rectangular sides, and three angles.There are 9 vertices, 6 edges, and 5 faces ". The answer to the …The area of the rectangular face = 20. The surface area of an equilateral triangular prism = Area of the top and base triangles + Area of the three rectangular faces. The surface area of an equilateral triangular prism = 2 × 60 + 3 × 20. Answer: The surface area of the equilateral triangular prism is 180 squared units.Apr 24, 2017 · By incorporating a triangle's area and perimeter formulas into the equation surface area = 2 * base triangle's area + triangle's perimeter * prism's height, you can easily calculate the surface area of tents and other triangular prisms. Multiply one of the triangular end's measurements of base and height together. The surface area of a closed cylinder can be calculated by summing the total areas of its base and lateral surface: base SA = 2πr 2. lateral SA = 2πrh. total SA = 2πr (r + h) where r is the radius and h is the height. Jeremy has a large cylindrical fish tank that he bathes in because he doesn't like showers or bathtubs.Example \(\PageIndex{4}\) Find the surface area of the prism below. Figure \(\PageIndex{11}\) Solution. This is a right triangular prism. To find the surface area, we need to find the length of the hypotenuse of the base because it …Explanation: . The surface area of the prism can be broken into three rectangular sides and two equilateral triangular bases. The area of the sides is given by: , so for all three sides we get . The equilateral triangle is also an equiangular triangle by definition, so the base has congruent sides of 6 in and three angles of 60 degrees.To find the area of the rectangular sides, use the formula A = lw, where A = area, l = length, and h = height. To find the area of the triangular faces, use the formula A = 1/2bh, where A = area, b = base, and h = height. Once you have the areas of all sides and faces, you simply add them together to get the surface area.This video demonstrates how to find the surface area of a triangular prism when it is in it's 3D form.#geometry#surfaceareaJan 30, 2024 · Surface area of a cylinder: A = 2πr² + 2πrh, where r is the radius and h is the height of the cylinder. Surface area of a cone: A = πr² + πr√ (r² + h²), where r is the radius and h is the height of the cone. Surface area of a rectangular prism (box): A = 2 (ab + bc + ac), where a, b and c are the lengths of three sides of the cuboid. Mar 24, 2021 ... Therefore, the formula for the surface area of a triangular prism is \[bh+lb+2ls\]. Note: students must know the concept of surface area.Surface area of a triangular prism. The surface area formula for a triangular prism is 2 * (height x base / 2) + length x width 1 + length x width 2 + length x base, as seen in the …Cam's tent (shown below) is a triangular prism. Created with Raphaël 1 m 1 m 3 m 2 m 2 m 1.7 m Find the surface area, including the floor, of his tent. / / ...Calculate the rectangular prism surface area. First rectangle area is 15in × 12in = 180in², second 15in × 18in = 270in² and third one 18in × 12in = 216in². Add all three rectangles' areas - it's equal to 666 in² ( what a number!) - and finally multiply by 2. The surface area of our cardboard box is 1332in². Or save yourself some time ...A triangular prism’s surface area is also known as its total surface area. It is equal to the sum of the areas of all its faces. Knowing the base, length and height of a triangular prism is all that is required to calculate its surface area. The total surface area of a triangular prism is equal to the sum of twice the base area and thrice the ...Surface area of a triangular prism. The surface area of a triangular prism is the sum of the areas of its 3 lateral faces and 2 bases and is given by the formula, where SA is surface area, a, b and c are the lengths of the sides of the bases, b is the bottom side of the base, and h is the height of the base. Types of triangular prismsSurface Area of a Triangular Prism When the Height of the Triangle Isn't Given. Part of the series: Finding and Using the Area of a Triangle. Just because th...A prism is a member of the polyhedron family consisting of two identical and parallel polygonal bases. The bases are connected by flat faces forming a uniform cross-section. In general, a prism refers to a …Calculate the area of each face and then add them together for the surface area of the rectangular prism. The surface area of the prism is the sum of the areas. Add each area twice, since each rectangle appears twice in the prism: 8+8+12+12+6+6=52 \, f t^2 . You can also find the surface area by multiplying each area by 2 and then adding.FlexBook Platform®, FlexBook®, FlexLet® and FlexCard™ are registered trademarks of CK-12 Foundation.The formula to calculate the surface area of a triangular prism is as follows: Surface Area = bh + (s1 + s2 + s3)l. Where b is the area of the base, h is the height of the …The Base Area (A b) of a triangular prism is : The Lateral Surface (A L) of a triangular prism is : The Surface Area (A s) of a triangular prism is : The Volume (V) of a triangular prism is : Triangular Prism Base Area Formula and Calculations; A b = 2a/b A b = 2 × / A b = 2 × A b = Triangular Prism Lateral Surface Formula and Calculations; A ...Using a net to find the surface area of a rectangular prism. Finding the areas of each of the rectangles and triangles of the net of a triangular prism and adding up those areas gives the surface area or total surface area of the triangular prism. For example, let the legs of a right triangle that is base of a triangular prism are 3 and 4 units ...Find the surface area of the triangular prism with the measurements seen in the image. Solution: From the image, we can observe that the side lengths of the triangle are a = 5 cm, b = 6 cm and c = 5 cm . Jan 18, 2024 · Note that A_b denotes the surface area of a single base of our prism. On the other hand, A_l denotes the lateral area, meaning the total area of the four lateral faces. Therefore, since the solid has two bases (the bottom one and the top one), the surface area of a rectangular prism formula is as follows: surface_area = 2 × base_area + lateral ... Learn how to find the surface area of a triangular prism by opening it up into a net and adding the areas of each of the five faces. Watch a video tutorial with step-by-step instructions and examples, and see the formula for the area of a triangle and a rectangle. Calculate the area of each face and then add them together for the surface area of the rectangular prism. The surface area of the prism is the sum of the areas. Add each area twice, since each rectangle appears twice in the prism: 8+8+12+12+6+6=52 \, f t^2 . You can also find the surface area by multiplying each area by 2 and then adding.Research shows that aid tends to flow to places that hold the relatively rich instead of poorer ones. The role of aid in Africa has been a controversial issue over the years, with ...In this lesson we show how to calculate the Total Surface Area of Rectangular and Triangular Prisms, including Cylinders, as well as the TSA of Pyramids. TSA of Rectangular Prisms. One method of calculating the TSA (Total Surface Area) is to “unfold” a 3D shape, into its flat “2D” net which the shape is made from.Learn how to calculate the surface area of triangular prisms.Use the formula 2 x one half base times height plus length times width in order to get the surfa...Aug 3, 2023 · The total surface area of a prism is the combined area of the 2 bases and the areas of the lateral faces. Since Lateral Surface Area (LSA) of a prism = Base perimeter x height. The lateral surface area is the area of all the faces except the bases. We can also write: Total Surface Area (TSA) = 2 × Base Area + LSA. Surface area of a triangular prism. The surface area of a triangular prism is the sum of the areas of its 3 lateral faces and 2 bases and is given by the formula, where SA is surface area, a, b and c are the lengths of the sides of the bases, b is the bottom side of the base, and h is the height of the base. Types of triangular prismsThis is a junior maths example of finding the surface area of a triangular prism. The triangle is isosceles and required the use of Pythagoras' theorem to fi...The height of each triangular face is 4 cm. Find the surface area of the triangular prism. 3 . A triangular prism has a right isosceles triangle as its base ...13.2 Right prisms and cylinders. A right prism is a geometric solid that has a polygon as its base and vertical faces perpendicular to the base. The base and top surface are the same shape and size. It is called a “right” prism because the angles between the base and faces are right angles. A triangular prism has a triangle as its base, a ...Mar 24, 2014 ... Surface Area of a Triangular Prism. 2.6K views · 9 years ago ...more. SmithMathAcademy. 26.4K. Subscribe.A triangular prism is a prism that has two congruent triangles as its bases connected by three rectangular lateral faces. The surface area of the triangular prism is the sum total of the areas of its bases and its lateral faces. Formula to find the surface area of a triangular prism. The Surface Area = 2 B + p h. where, B is the area of the ... Mar 24, 2021 ... Therefore, the formula for the surface area of a triangular prism is \[bh+lb+2ls\]. Note: students must know the concept of surface area.Like so: To calculate the surface area of a triangular prism, we need to add the areas of all the shapes that make up this prism. First of all, we need to cover the ground. We can see that this is a rectangle. .. The area of …Thus, the surface area of an equilateral triangular prism is calculated by adding up the area of all rectangular and triangular faces. The surface area of an ...To calculate the surface area of a triangular prism, find the area of each face and add them all together. Lateral faces are all of the faces of an object excluding the top and the base. For a triangular prism the top and the base are triangles and the lateral faces are rectangular sides. May 7, 2019 ... So if we find the area of each of these shapes and we add them together, we will have the surface area. The area of a triangle is one-half times ...Mar 27, 2022 · Because a net shows all the faces of a polyhedron, we can use it to find its surface area. For instance, the net of a rectangular prism shows three pairs of rectangles: 4 units by 2 units, 3 units by 2 units, and 4 units by 3 units. Figure \(\PageIndex{9}\) The surface area of the rectangular prism is 52 square units because \(8+8+6+6+12+12=52\). Jan 18, 2024 · Note that A_b denotes the surface area of a single base of our prism. On the other hand, A_l denotes the lateral area, meaning the total area of the four lateral faces. Therefore, since the solid has two bases (the bottom one and the top one), the surface area of a rectangular prism formula is as follows: surface_area = 2 × base_area + lateral ... A prism is a solid figure with flat faces, two identical bases, and with the same cross-section all along its length. The name of a particular prism depends on the two bases of the prism which can be triangles, rectangles, or any polygon.For example, a prism with triangular bases is called a triangular prism and a prism with a square base is …Now, because the surface area is the total area used to form the faces of a 3-D shape, we must add all the areas of the figures together. Area of a triangle (modified) A=2(1/2•3•4) Area of rectangle: A=12•2 Simplify: Triangle: A=2(6) A=12 Rectangle: A=12•2 A=24 Now, let’s add the areas together: 12+24=36 So, the surface area is 36ft^2.Mar 27, 2022 · Because a net shows all the faces of a polyhedron, we can use it to find its surface area. For instance, the net of a rectangular prism shows three pairs of rectangles: 4 units by 2 units, 3 units by 2 units, and 4 units by 3 units. Figure \(\PageIndex{9}\) The surface area of the rectangular prism is 52 square units because \(8+8+6+6+12+12=52\). Formula to find the surface area of a triangular prism is given by: where, b = Triangle base length. h = Triangle height. H = Prism height. S1 = Side 1 of the triangle. S2 = Side 2 of the triangle. S3 = Side 3 of the triangle. In the below online surface area of a triangular prism calculator, enter the above mentioned parameters in the input ...Example 5. Find the total surface area of a hexagonal prism whose apothem length, base length, and height are given as 7 m, 11 m, and 16 m, respectively. Solution. The total surface area formula for a hexagonal prism is given as: TSA = 6ab + 6bh. Substitute. TSA = 6 x 7 x 11 + 6 x 11 x 16. = 462 + 1056. Note that A_b denotes the surface area of a single base of our prism. On the other hand, A_l denotes the lateral area, meaning the total area of the four lateral faces. Therefore, since the solid has two bases (the bottom one and the top one), the surface area of a rectangular prism formula is as follows: surface_area = 2 × base_area + lateral ...What is Triangular prism? A triangular prism is a three-sided prism; it is a polyhedron made of a triangular base, a translated copy, and 3 faces joining corresponding sides. Given figure is a right angled triangular prism. Total surface area of the right angle triangular prism = (x + y + h )L + b × h. Here, x= 8 cm. y= 10 cm. h= 6 cm. L= 4 cm ...Learn how to calculate the surface area of a triangular prism using a simple formula that combines the areas of the base triangle and the three rectangular faces. See how …To calculate the surface area of the triangular prism, calculate the area of each face and then add them together. The surface area of the prism is the sum of the areas. Add the …Find the surface area of the triangular prism with the measurements seen in the image. Solution: From the image, we can observe that the side lengths of the triangle are a = 5 cm, b = 6 cm and c = 5 cm . area = length * (a + b + c) + (2 * base_area), where a, b, c are sides of the triangle and base_area is the triangular base area But what if we don't have the height …Oct 24, 2016 ... How to find the total surface area of a triangular prism.Apr 25, 2023 · To find the surface area of triangular prism, you first need to find the area of the lateral sides, then you need to find the area of the bases. Finally, you need to add these two areas together to find the total surface area. These steps are represented by the formula , where equals the lateral area of the prism and equals the area of one base. Surface Area of a Triangular Prism. The surface area of a triangular prism is the area that is occupied by its surface. It is the sum of the areas of all the faces of the prism. Hence, the formula to calculate the surface area is: Surface area = (Perimeter of the base × Length) + (2 × Base Area) = (a + b + c)L + bh. where, This video shows how to find the surface area of prisms such as a triangular prism and a trapezoid prism. Ideal for GCSE maths. On www.corbettmaths.com/conte...Like so: To calculate the surface area of a triangular prism, we need to add the areas of all the shapes that make up this prism. First of all, we need to cover the ground. We can see that this is a rectangle. .. The area of …To find the surface area of a triangular prism, you start by finding the area of each triangle (base times height divided by two) and then adding those together ...Find the surface area of the triangular prism with the measurements seen in the image. Solution: From the image, we can observe that the side lengths of the triangle are a = 5 cm, b = 6 cm and c = 5 cm . The surface area of the right-angled triangular prism is 123.31. Triangular Prism Surface Area Example Problem 2. If we are given a triangular prism that has a ...The surface area consists of the area of the two triangles, plus the area of the three rectangles. It can help to draw the shapes separately. The diagram shows ...The figure presents a surface net of a rectangular prism. The net consists of 4 rectangles in a row, where the second rectangle from the left is also connected to a rectangle above it and a rectangle below it. The bottom of the left most rectangle is labeled as 3 units. The bottom of the second rectangle from the left is labeled as 2 units. The figure presents a surface net of a rectangular prism. The net consists of 4 rectangles in a row, where the second rectangle from the left is also connected to a rectangle above it and a rectangle below it. The bottom of the left most rectangle is labeled as 3 units. The bottom of the second rectangle from the left is labeled as 2 units.This video continues with the concept of surface area by looking at an example problem which asks to find the surface area of an equilateral triangular prism... The surface area of a triangular prism is the total area of all of the faces. To calculate the surface area of a triangular prism, find the area of each face and add them all together. Lateral faces are all of the faces of an object excluding the top and the base. For a triangular prism the top and the base are triangles and the lateral faces ...Want to know how the find the lateral and surface areas of a triangular prism? Then check out this tutorial! ... You'll see how to apply each formula to the given information to find the lateral area and surface area. Take a look! Keywords: triangular prism; prism; lateral area; surface area; solve; formula; triangle; base; lateral face; area;Surface area formulas for prisms. For every 3D solid, we can examine each face or surface and calculate its surface area. Then, adding all the individual surface areas, we can find the surface area of the entire solid. Think of it as unfolding the 3D shape like a cardboard box. Lay out every face, measure each, and add them.The surface area of a prism is the sum of the areas of all its faces. The Surface Area of a Prism Formula depends on the shape of the base. A prism is a three-dimensional solid with two identical polygonal bases connected by parallelogram lateral faces.. In this maths formula article, we will learn surface area of a prism formula and …Learn how to calculate the surface area of a triangular prism using different formulas and methods, with over 15 units to choose from. Enter some numbers and get …Area is the space within the perimeter of a two-dimensional figure. A prism is a three-dimensional object with two congruent parallel bases that are polygons. Surface area is the total area of all of the surfaces of a three-dimensional object. A triangular prism is a prism made up of two triangular bases and three rectangular faces. Jul 24, 2020 · How to Find the Surface Area of a Triangular Prism | Math with Mr. J Math with Mr. J 1.04M subscribers Subscribe Subscribed 8.8K 948K views 3 years ago Measurement and Data Welcome to How to... A triangular prism’s surface area is also known as its total surface area. It is equal to the sum of the areas of all its faces. Knowing the base, length and height of a triangular prism is all that is required to calculate its surface area. The total surface area of a triangular prism is equal to the sum of twice the base area and thrice the ...Lateral Surface Area = 12(8) = 96 inches2 = 12 ( 8) = 96 inches 2. The general formula for the total surface area of a right prism is T. S. A. = ph + 2B T. S. A. = p h + 2 B where p p represents the perimeter of the base, h h the height of the prism and B B the area of the base. There is no easy way to calculate the surface area of an oblique ... Like so: To calculate the surface area of a triangular prism, we need to add the areas of all the shapes that make up this prism. First of all, we need to cover the ground. We can see that this is a rectangle. .. The area of …Test your understanding of Volume and surface area with these % (num)s questions. Start test. Volume and surface area help us measure the size of 3D objects. We’ll start with the volume and surface area of rectangular prisms. From there, we’ll tackle trickier objects, such as cones and spheres. This video demonstrates how to find the surface area of a triangular prism when it is in it's 3D form.#geometry#surfaceareaThe height of the triangular prism = 10 cm. Thus, the lateral area of triangular prism = (a + b + c ) h. = (3 + 6 + 7) 10. = (16) 10. = 160 cm 2. Answer: The lateral area of the given triangular prism = 160 cm 2. Example 2: The perimeter of a triangular prism is 108 units and its lateral surface area is 756 units. Surface area of a triangular prism. The surface area formula for a triangular prism is 2 * (height x base / 2) + length x width 1 + length x width 2 + length x base, as seen in the figure below: A triangular prism is a stack of triangles, so the usually triangle solving rules apply when calculating the area of the bases. What is Triangular prism? A triangular prism is a three-sided prism; it is a polyhedron made of a triangular base, a translated copy, and 3 faces joining corresponding sides. Given figure is a right angled triangular prism. Total surface area of the right angle triangular prism = (x + y + h )L + b × h. Here, x= 8 cm. y= 10 cm. h= 6 cm. L= 4 cm ...A triangular prism is a prism that has two congruent triangles as its bases connected by three rectangular lateral faces. The surface area of the triangular prism is the sum total of the areas of its bases and its lateral faces. Formula to find the surface area of a triangular prism. The Surface Area = 2 B + p h. where, B is the area of the ... Explanation: To calculate the surface area of a triangular prism, We will use the formula: bh + l (a+b+c) square units. where, b = base length of the triangle. h = height of the triangle. l = distance between triangular bases. a, b, c = sides of the triangle.Get your free lessons: https://vividmath.comHow to find the Surface Area of a Triangular Prism. See all Surface Area lessons: https://vividmath.com/geometry/...Apr 20, 2012 ... Get your free lessons: https://vividmath.com How to find the Surface Area of a Triangular Prism. See all Surface Area lessons: ...
In this lesson we show how to calculate the Total Surface Area of Rectangular and Triangular Prisms, including Cylinders, as well as the TSA of Pyramids. TSA of Rectangular Prisms. One method of calculating the TSA (Total Surface Area) is to “unfold” a 3D shape, into its flat “2D” net which the shape is made from.. Keesler federal credit union near me
Plug the decimal dimensions in SA = bh + (s1 + s2 + s3)H, where 'b' and 'h' are the base length and height of the triangle; 's1', 's2', and 's3&...Find surface area of triangular prisms. Let’s Get Started: Watch Video: Triangular Prism. Practice: Heights of Triangles In all of the triangles below, h (height) is the same, but in different locations. For a right triangle, the height is one of the legs because they are already perpendicular to eachJan 18, 2024 · Note that A_b denotes the surface area of a single base of our prism. On the other hand, A_l denotes the lateral area, meaning the total area of the four lateral faces. Therefore, since the solid has two bases (the bottom one and the top one), the surface area of a rectangular prism formula is as follows: surface_area = 2 × base_area + lateral ... Nov 30, 2023 · FlexBook Platform®, FlexBook®, FlexLet® and FlexCard™ are registered trademarks of CK-12 Foundation. The formula for finding a triangular prism's volume is the area of the triangle (Width x Height x 1/2) times the depth. The formula for finding a cube's volume is Base x Height ... where you really just want to find the area of this surface right over here. Now, this is pretty straightforward. This is just a square, or it would be the base ...Explanation: To calculate the surface area of a triangular prism, We will use the formula: bh + l (a+b+c) square units. where, b = base length of the triangle. h = height of the triangle. l = distance between triangular bases. a, b, c = sides of the triangle.This video continues with the concept of surface area by looking at an example problem which asks to find the surface area of an equilateral triangular prism... Want to know how the find the lateral and surface areas of a triangular prism? Then check out this tutorial! ... You'll see how to apply each formula to the given information to find the lateral area and surface area. Take a look! Keywords: triangular prism; prism; lateral area; surface area; solve; formula; triangle; base; lateral face; area;This video continues with the concept of surface area by looking at an example problem which asks to find the surface area of an equilateral triangular prism... Nov 21, 2023 · To find the surface area of a triangular prism, we simply add up the areas of both bases and all three faces. We can also use the following formula to find this surface area. Area is the space within the perimeter of a two-dimensional figure. A prism is a three-dimensional object with two congruent parallel bases that are polygons. Surface area is the total area of all of the surfaces of a three-dimensional object. A triangular prism is a prism made up of two triangular bases and three rectangular faces. To find the surface area of a prism or a cylinder, calculate the top and bottom base areas and side area, respectively, and add the numbers. ... First, let’s calculate the side area. The length of the triangular prism’s ….
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Project 64 download | Surface Area of a Triangular Prism When the Height of the Triangle Isn't Given. Part of the series: Finding and Using the Area of a Triangle. Just because th...Example: What is the surface area of a prism where the base area is 25 m 2, the base perimeter is 24 m, and the length is 12 m: Surface Area = 2 × Base Area + Base Perimeter × Length. = 2 × 25 m2 + 24 m × 12 m. = 50 …...
Buy fruits online tirunelveli district online | Method to calculate the total surface area of a triangular face. To calculate the total surface area of a triangular face, you must know the base of the prism. There are two bases that are congruent to each other. Typically, the base is a square or a triangle. Each base has a height and an altitude.3996. What is the surface area? 5920. What is the surface area? 588. What is the surface area? 790. What is the surface area? 384. ...
Partido mexico hoy | Learn how to find the surface area of a triangular prism by opening it up into a net and adding the areas of each of the five faces. Watch a video tutorial with step-by-step instructions and examples, and see the formula for the area of a triangle and a …Dec 26, 2023 · To find the volume of a prism, multiply the area of the prism’s base times its height. This is written as V = Bh V = B h. Notice that big B stands for area of the base. It is important that you capitalize this B because otherwise it simply means base. We see this in the formula for the area of a triangle, ½ bh. ...
Detroit lions rumors | How to calculate the surface area of a prism · Work out the area of each rectangle separately, length × width. · Multiply the perimeter of the end face by the .....Surface area using a net: triangular prism. Surface area using a net: rectangular prism. Surface area of a box (cuboid) ... In a previous video, we figured out how to find the surface area of this cereal box by figuring out the areas of each of the six surfaces of the box and then adding them all up. I'm gonna do that again in this video, but I ......
Mauga voice actor | About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright ...Surface area is the total area of the two dimensiona... In this video you will learn how to find the surface area of a rectangular prism and a triangular prism....
The flow hair | To find the total surface area of a triangular prism, we need to calculate the area of all its faces. This includes the areas of the two triangular bases and the three rectangular sides. The given dimensions do not directly fit a standard triangular prism as there is no information provided about the dimensions of the triangular bases or how ...Get your free lessons: https://vividmath.comHow to find the Surface Area of a Triangular Prism. See all Surface Area lessons: https://vividmath.com/geometry/......