What am I missing here? ("Easy" math problem)

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1

<p>So, this is #6 in a practice test:</p>

<p>(Pretend there's a trapezoid drawn here). The upper base and lower base are parallel, the right-hand side is the height, and the left-hand side is a slant.</p>

<p>Upper base: 20
Height: 15
Slant: 17</p>

<p>What is the perimeter?</p>

<p>The answer is (d) 80. I don't get it.</p>

2

<p>First solve for the bottom length</p>

<p>Use pythagorean theorem. Look for a triangle, and solve for bottom for the extra length.</p>

<p>(17^2)-(15^2)= Square of 64=8 is the extra length attached to 20</p>

<p>28+20+15+17=80
Bottom Length=28
Top=20
Height/Side=15
Slant=17</p>