SOLUTION: The area of a rectangle is 53m^2 and the length of the rectangle is 5 m less than twice the width, find the dimensions of the rectangle

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Question 1170681: The area of a rectangle is 53m^2 and the length of the rectangle is 5 m less than twice the width, find the dimensions of the rectangle

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

The area of a rectangle is 53m%5E2:
L%2AW=53
and if the length L of the rectangle is 5m less than twice the width W, we have
L=2W-5....substitute in area
%282W-5%29%2AW=53
2W%5E2-5W=53
2W%5E2-5W-53=0

W+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
W+=+%28-%28-5%29+%2B-+sqrt%28+%28-5%29%5E2-4%2A2%2A%28-53%29+%29%29%2F%282%2A2%29+
W+=+%285+%2B-+sqrt%28+25%2B424+%29%29%2F4+
W+=+%285+%2B-+sqrt%28+449+%29%29%2F4+
W+=+%285+%2B-+21.19%29%2F4+
solutions: need only positive
W+=+%285+%2B+21.19%29%2F4+
W+=+6.55
go to
L=2W-5 substitute W
L=2%2A6.55-5
L=8.1

the dimensions of the rectangle are approximately 8.1 by +6.55