SOLUTION: The base of an isosceles trapezoid measure 32cm and 20cm. find the area if the non-parallel sides measure 16cm each.

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Question 1111551: The base of an isosceles trapezoid measure 32cm and 20cm. find the area if the non-parallel sides measure 16cm each.
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Two congruent right triangles of height h at each side
Height of trapezoid is sqrt%28220%29.
(Pythagorean Theorem)

sqrt%28220%29%2A%2832%2B20%29%2F2
sqrt%28220%29%2A26
sqrt%2811%2A4%2A5%29%2A26
2%2Asqrt%2811%2A5%29%2A26
52%2Asqrt%2855%29

Answer by ikleyn(52786) About Me  (Show Source):
You can put this solution on YOUR website!
.
Draw the altitude to the base from the vertex.


Then you will get a right angled triangle with the hypotenuse of 16 cm long.


The length of one leg is  %2832-20%29%2F2 = 6 cm.


Then the altitude is sqrt%2816%5E2+-+6%5E2%29 = sqrt%28256-36%29 = sqrt%28220%29 = 2%2Asqrt%2855%29.


The area of the trapezoid is  2%2Asqrt%2855%29%2A%28%2832%2B20%29%2F2%29 = 52%2Asqrt%2855%29 cm^2.

Solved.

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Be aware:  The solution and the answer by the @josgarithmetic are   W R O N G.