I HATE how to find the surface area of a triangular prism!! Anyone have an easy way to find surface area of a triangular prism ??

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sciencesolve | Teacher | (Level 3) Educator Emeritus

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The surface area of the triangular prism is calculated as a sum of areas of the base, floor and walls. Since the base and floor are two equal triangles, you may write the surface area of triangular prism such that:

`SA` = 2Base area +` l_1*H + l_2*H + l_3*H`

`l_1,l_2,l_2` represent the lengths of the sides of base triangle

H represents the height of the prism

Base area = `(l_1*h)/2`

h represents the height of base triangle

You may notice that you may factor out the height of prism H, such that:

`SA= 2*(l_1*h)/2 + H*(l_1+l_2+l_3)`

Reducing the like factors and replacing the sum of sides of triangular base, `l_1+l_2+l_3` , by the perimeter P of triangular base, yields:

`SA= l_1*h + H*P`

Hence, evaluating the surface area of triangular prism, yields `SA= l_1*h + H*P.`

Sources:
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taangerine | Student, Grade 12 | (Level 1) Valedictorian

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Plug the length, width, height, and side into this formula : SA = hw + wl + lh + ls to find the Surface area of the triangular prismĀ 

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givingiswinning | Student, Grade 10 | (Level 1) Valedictorian

Posted on

use the formula SA = wh + lw + lh + lsĀ 

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atyourservice | Student, Grade 11 | (Level 3) Valedictorian

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SA = wh + lw + lh + ls , just use this formula, i am guessing this is probably the one you are complaining about. But just try to work with it, the more you use it the easier it becomes for you to understand.

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