SOLUTION: If the diagonal of a rectangle is 15 and the perimeter of the rectangle is 42, what is the area.

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Question 329432: If the diagonal of a rectangle is 15 and the perimeter of the rectangle is 42, what is the area.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Diagonal:
D%5E2=L%5E2%2BW%5E2=15%5E2
.
.
Perimeter:
2%28L%2BW%29=42
L%2BW=21
.
.
Area:
A=LW
.
.
.
%28L%2BW%29%5E2=L%5E2%2B2LW%2BW%5E2
%28L%2BW%29%5E2=%28L%5E2%2BW%5E2%29%2B2LW
21%5E2=15%5E2%2B2A
2A=21%5E2-15%5E2
A=%281%2F2%29%2821%5E2-15%5E2%29
A=%281%2F2%29%28441-225%29
A=%281%2F2%29%28216%29
A=108