SOLUTION: The length of a rectangle is 3 ft longer than its width. If the perimeter of the rectangle is 70ft, find its length and width.

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Question 1132938: The length of a rectangle is
3 ft longer than its width.
If the perimeter of the rectangle is
70ft, find its length and width.

Found 2 solutions by addingup, MathLover1:
Answer by addingup(3677) About Me  (Show Source):
You can put this solution on YOUR website!
L = W + 3
2(W + 3) + 2W = 70
2W + 6 + 2W = 70
4W = 64
W = 16
and the length is:
L = 16 + 3 = 19
~~~~~~~~~~~~~~~~~~~~~
Check:
2L + 2W = 70
2(19) + 2(16) = 70
38 + 32 = 70 Correct

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

if the length L of a rectangle is 3ft longer than its width W, we have
L=W%2B3ft.......eq.1
if the perimeter P of the rectangle is 70ft, we have
P=2%28L%2BW%29
70ft=2%28L%2BW%29

70ft%2F2=L%2BW
35ft=L%2BW ......eq.2
substitute L from eq.1
35ft=W%2B3ft%2BW ......eq.2
35ft-3ft=2W
32ft=2W
W=++32ft%2F2
W=+16ft
go back to eq.1,substitute W
L=16ft%2B3ft.......eq.1
L=19ft

answer: its length is 19ft and width is +16ft