Answer:
The width of the sidewalk should be 5.4 feet.
Step-by-step explanation:
The dimension of his pool = 60 ft × 40 ft. So that the area of his pool = 2400 . But he has enough pavers to cover 1200
Let the width of the sidewalk be represented by w. Thus,
(60 + 2w)(40+ 2w) - 60(40) = 1200
2400 + 120w + 80w + 4 -2400 = 1200
2400 + 200w + 4 -2400 = 1200
4 + 200w -1200 = 0
Divide through by 4, to have;
+ 50w - 300 = 0
Solving the quadratic equation by formula, we have;
w = (-b ± ) ÷ 2a
where from the equation; a = 1, b= 50 and c= -300. Substituting these in the expression gives,
w = (-50±) ÷ 2*1
w = (-50±60.8276) ÷ 2
w = (-50+60.8276) ÷ 2 or (-50-60.8276) ÷ 2
w = or
w = 5.4138 or -55.4138
w = 5.4138
Therefore, the width of the sidewalk should be 5.4 feet.