SOLUTION: The length and width of a rectangular sheet of plywood is 4 ft. by 8 ft, how much must be added equally to the length and width to double the area? (Answer to the nearest tenth of

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Question 825847: The length and width of a rectangular sheet of plywood is 4 ft. by 8 ft, how much must be added equally to the length and width to double the area? (Answer to the nearest tenth of a foot.)
Let x = the amount added
Found 2 solutions by phoihe001, josgarithmetic:
Answer by phoihe001(34) About Me  (Show Source):
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
4%2A8=32%2Aft%5E2 original area.
Doubled area wanted is 2%2A32=64%2Aft%5E2.

Increase both dimensions each by x.
%28x%2B4%29%28x%2B8%29=64
'
x%5E2%2B12x%2B32=64
x%5E2%2B12x-32=0....... Is this factorable or not? If not, use general solution to a quadratic equation.