I can't explain much but here is how to solve that.
The formula for the are of a rectangle is A = LW
Width = w
Length = 8m longer than the width = w + 8
Area of the swimming pool = Length x Width = 105
= w + 8 ( w)
= w² + 8w
= w² + 8w = 105
w² + 8w - 105 = 0
(Factor this out)
w² + 8w - 105 = 0
( w + 15 ) (w - 7) = 0
w + 15 = 0, w - 7 = 0
w = -15, w = 7
Since there is no -15m in length, then the length and width is:
Length of the swimming pool = 15m
Width of the swimming pool = 7m
Overall, they are equal to: 15m x 7m = 105, CORRECT
15m - 7m = 8m, CORRECT
