SOLUTION: The length of rectangle is 7 m less than twice the width. If the length is decreased by 1m and the width by 4 m, the perimeter will be 66. Find the dimensions of the original rect

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Question 338823: The length of rectangle is 7 m less than twice the width. If the length is decreased by 1m and the width by 4 m, the perimeter will be 66. Find the dimensions of the original rectangle.
Thank you so much for helping
Alena
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
The length of rectangle is 7 m less than twice the width. If the length is decreased by 1m and the width by 4 m, the perimeter will be 66. Find the dimensions of the original rectangle.
.
Let w = width
then
from: "length of rectangle is 7 m less than twice the width"
2w-7 = length
.
Length decreased by 1 m:
2w-7-1 = 2w-8
.
Width decreased by 4 m:
w-4
.
2(width + length) = perimeter
2(w-4 + 2w-8) = 66
dividing both sides by 2:
w-4 + 2w-8 = 33
3w-12 = 33
3w = 45
w = 15 meters (width)
.
length:
2w-7 = 2(15)-7 = 30-7 = 23 meters (length)
.
dimensions:
15 by 23 meters