How do you find the area of a trapezoid when you have the length of every side but not the height?

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Answer 1 · 2015-11-14T16:24:12

$(B+b)/(B-b) cdot Delta$

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The triangle area is $Delta = 1/2 (B - b) h = sqrt{p(p-x)(p-y)(p-B+b)}$

$2p = x + y + B - b$

This is Heron's formula. Solve for $h = (2Delta)/(B-b)$

Area of trapezoid = $(B + b)/2 cdot h$

$= (B + b)/(B - b) cdot sqrt{p(p-x)(p-y)(p-B+b)}$