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Question

Find the dimensions of a rectangle whose width is 5 miles less than its length, and whose area is 104 square miles.

Answer 1

A = L x w

you can substitute the info they give you for width and area

104 = L x (L - 5)

104 = L^2 - 5L      L^2 means L squared

-104             -104

0 = L^2 - 5L - 104

0 = (L+8) (L-13)

L+8 = 0   or   L-13 = 0

L=-8        or  L=13

 

length can't be a negative number, so the LENGTH IS 13 MILES

since width is 5 less than that, WIDTH IS 5 MILES