Question 243535
8*10=80 yds^62 is the area of the pool.
(8+2x)(10+2x)=120
80+20x+16x+4x^2=120
4x^2+36x+80-120=0
4x^2+36x-40=0
4(x^2+9x-10)=0
4(x+10)(x-1)=0
x-1=0
x=1 yd. is the width of the deck.
Proof:
(8+2*1)(10+2*1)=120
(8+2)(10+2)=120
10*12=120
120=120