Question 281320
let length be x

width =y

x*y=15

2x+2y=16

x+y=8

x=8-y

xy=15

y(8-y)=15

8y-y^2-15=0

y^2-8y+15=0

y^2-5y-3y+15=0

y(y-5)-3(y-5)=0

(y-3)(y-5)=0

y=3  , 5  


the sides are 3 & 5  feet