SOLUTION: A rectangle is 5cm longer than double its width. Its area is 75cm^2. What are the dimensions of the rectangle?

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Question 950751: A rectangle is 5cm longer than double its width. Its area is 75cm^2. What are the dimensions of the rectangle?
Found 2 solutions by Fombitz, MathTherapy:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
For a rectangle,
A=L%2AW
L%2AW=75
%28W%2B5%29W=75
W%5E2%2B5W=75
W%5E2%2B5W%2B%285%2F2%29%5E2=75%2B%285%2F2%29%5E2
%28W%2B5%2F2%29%5E2=300%2F4%2B25%2F4
%28W%2B5%2F2%29%5E2=325%2F4
W%2B5%2F2=0+%2B-+sqrt%28325%29%2F2
W=-5%2F2%2B-+%285%2F2%29sqrt%2813%29
Only the positive solution makes sense here,
W=-5%2F2%2B%285%2F2%29sqrt%2813%29
So then,
L=5-5%2F2+%2B+%285%2F2%29sqrt%2813%29
L=5%2F2+%2B+%285%2F2%29sqrt%2813%29

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

A rectangle is 5cm longer than double its width. Its area is 75cm^2. What are the dimensions of the rectangle?
Width:    highlight_green%285%29 cm

Length: highlight_green%2810%29 cm

You can do the check!! 

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