Question

Rectangular garden 60 ft x 80 ft surrounded by a walk of uniform width. The area of the walk is 7,200 ft^2. Find the width, x, of the walk.

Answer 1

since the garden is surrounded on all sides by a walk of uniform width x
then the outer length becomes x+80+x = 80+2x
and outer width becomes x+60+x = 60+2x
area of the walk = outer area - inner area
thus we have
7200 = (80+2x)*(60+2x) - 60*80
7200 = 80*60 +2x*80 + 2x *60 +4x^x -60*80

i hope u can do further...