Question 977552: The perimeter of a rectangle is 18 ft. The area of the rectangle is 14 square feet. what is the width of the rectangle? Answer by Cromlix(4381) (Show Source):
You can put this solution on YOUR website! Hi there,
Perimeter = 2xLength + 2xWidth
18 = 2xLength + 2xWidth
.................
Area = Length x Width
14 = L x W
Therefore Width = 14/L
................
Substitute W = 14/L
into:
18 = 2L + 2(14/L)
18 = 2L + 28/L
Multiply through by L
18L = 2L^2 + 28
Sort into equation in L
2L^2 - 18L + 28 = 0
Divide through by 2
L^2 - 9L + 14 = 0
Factorise
(L - 2)(L - 7) = 0
Either Length = 7ft and Width = 2ft
or
Length = 2ft and Width = 7ft
Hope this helps:-)
