Question 167432
the walk is on all four sides of the pool, so the dimensions of the pool are 20-2w and 22-2w
__ where w is the width of the walk


(20-2w)(22-2w)=323 __ 440-84w+4w^2=323 __ 4w^2-84w+117=0


use quadratic formula to find w





answer below



w=1.5