SOLUTION: The diagonal of a rectangle is 15 feet and the width is 9 feet. Find the area of the rectangle

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Question 821306: The diagonal of a rectangle is 15 feet and the width is 9 feet. Find the area of the rectangle
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
The diagonal splits the rectangle into two congruent right triangles.
In each of those triangles, the hypotenuse is the diagonal of the rectangle,
one leg is the width of the rectangle,
and the other leg in the length of the rectangle.
If the length is xfeet , according to the Pythagorean theorem,
x%5E2%2B9%5E2=15%5E2
x%5E2%2B81=225
x%5E2=225-81
x%5E2=144
x%5E2=12%5E2
So the length of the rectangle is 12+feet .
x=-12 is another solution of x%5E2=12%5E2 , but lengths are never negative numbers.

The area of a rectangle with a length of 12+feet and a width of 9+feet is
%289feet%29%2812+feet%29=highlight%28108%29squarefeet .