Dma 040
posted by Bridget .
Lenth of a rectangle is 7ft longer than twice the width. If the rooms perimeter is 158ft, whay are the rooms dimensions?
Width
Length

Represent the unknowns with variables:
Let x = width
Let 2x + 7 = length (according to the first statement)
Then we set up the equation. To set up, we need to recall that the perimeter of a rectangle is given by
P = 2L + 2W
where L is length and W is width.
We know that P = 158. Substituting,
158 = 2(2x + 7) + 2x
We solve for x:
158 = 4x + 14 + 2x
158  14 = 6x
144 = 6x
x = 144/6
x = 24 ft (width)
2x+7 = 55 ft (length)
hope this helps~ :3