What is the surface area formula for a trapezoidal prism?

1 Answer
Apr 20, 2018

S = a(h + l) + b(h + l) + cl + dl

Explanation:

Given: a trapezoidal prism

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The base of a prism is always the trapezoid for a trapezoidal prism.

The surface area S = 2*A_(Base) + "Lateral Surface Area"

A_(trapezoid) = A_(Base) = h/2 (a + b)

L = "Lateral Surface Area" = the sum of the areas of each surface around the Base.

L = al + cl + bl + dl

Substitute each piece into the equation:
S = 2*h/2 (a + b) + al + cl + bl + dl

Simplify:
S = h(a + b) + al + cl + bl + dl

Distribute and Rearrange:
S = ha +hb + al + cl + bl + dl

S = a(h + l) + b(h + l) + cl + dl