SOLUTION: A factory is to be built on a lot that measures 80m by 60m. A lawn of uniform width and equal in area of the factory must surround the factory. What dimensions must the factory hav

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons -> SOLUTION: A factory is to be built on a lot that measures 80m by 60m. A lawn of uniform width and equal in area of the factory must surround the factory. What dimensions must the factory hav      Log On


   

Question 871470: A factory is to be built on a lot that measures 80m by 60m. A lawn of uniform width and equal in area of the factory must surround the factory. What dimensions must the factory have?
Using quadratic equations and the quadratic formula (grade 10)
Answer by josgarithmetic(39615) About Me  (Show Source):
You can put this solution on YOUR website!
80 and 60 dimensions of lot.
Lot, 80*60 is the area.
Let w = uniform width surrounding the factory.
Factory area = (80-2w)(60-2w).

Factory and lawn of uniform width are equal in area. Think carefully about this. The lot area is TWO times the factory area.

%2880%2A60%29%2F%28%2880-2w%29%2860-2w%29%29=2
Or depending how best you think this,
80%2A60=2%2880-2w%29%2860-2w%29

Solve for w and use the value to find the dimensions of the FACTORY.