Answer:
12
Explanation:
GIven: an isosceles trapezoid ABCD with AD = 28, BC = 12, and BE = 9.
We can see that triangle BEA is a right triangle, so let's use the Pythagorean Theorem to solve for length AB.
To use the Pythagorean Theorem, we need the lengths of both legs. But we only have one! So let's solve for AE.
Now we know the lengths of both legs of right triangle BEA, so let's use the Pythagorean Theorem to solve for the hypotenuse, AB!
Pythagorean Theorem: where
and
are the legs and
is the hypotenuse.
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