SOLUTION: The length of a rectangle is 16 centimeters, and the diagonal of the rectangle is 20 centimeters long. What is the perimeter of the rectangle?

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Question 720543: The length of a rectangle is 16 centimeters, and the diagonal of the rectangle is 20 centimeters long. What is the perimeter of the rectangle?
Answer by ramsinaaa(9) About Me  (Show Source):
You can put this solution on YOUR website!
use pythagorean theorem to solve for the width of the rectangle.
a^2+b^2=c^2
16^2+b^2=20^2
256+b^2=400
b^2=144
b=12

length=16 width=12
2(length+width)=perimeter
2(16+12)
2(28)
perimeter=56