Answer:
The width of the floor is 10 ft.
Step-by-step explanation:
First, you have to form expressions of width and length in terms of w. With the given information :
width = w ft
length = (w - 2) ft
Given that the area of rectange is A = length × width so you have to subtitute the expressions and value into the formula :
A = l × w
80 = (w - 2) × w
w(w - 2) = 80
w² - 2w = 80
w² - 2w - 80 = 0
(w + 8)(w - 10) = 0
w + 8 = 0
w = -8 (rejected)
w - 10 = 0
w = 10
