SOLUTION: A factory is built on a lot that measures 80m by 60m. A lawn of uniform width will surround the factory. If the area of the combined factory and lawn is double the area of the fact

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Question 974015: A factory is built on a lot that measures 80m by 60m. A lawn of uniform width will surround the factory. If the area of the combined factory and lawn is double the area of the factory, find the width of the lawn to one decimal.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Dimensions of Factory: x and y.
Uniform Width of Lawn Around Factory: w.
Total Area Combined: (x+2w)(y+2w).
Area of Just Factory: xy.
Description means, (x+2w)(y+2w)=2xy.

Known Variables,
x=80
y=60
-
Unknown Variable,
w

Solve this for w.
highlight_green%28%28x%2B2w%29%28y%2B2w%29=2xy%29. It will be a quadratic equation. Go as far as you can purely in symbols before substituting for x and y to evaluate w.