Question 284241
Find x.

Here's another way to solve for x.

Let x = width of walkway

(12 - 2x)(15 - 2x) = total area or 180

180 - 54x + 4x^2 = 180

180 - 180 - 54x + 4x^2 = 0

-54x + 4x^2 = 0

x = 27/2