SOLUTION: The perimeter of a rectangle is 70. One side of the rectangle is 3 times the lenth of the other. What are the lenths of the sides?

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Question 279796: The perimeter of a rectangle is 70. One side of the rectangle is 3 times the lenth of the other. What are the lenths of the sides?
Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
What we know:
p=2l+2w
p=70
l=3w
What we need to find:
w=
l=
Use substitution to find w
p=2l+2w
70=2%283w%29%2B2w
70=6w%2B2w
70=8w
highlight%2835%2F4=w%29
l=3w
l=3%2835%2F4%29
highlight%28l=105%2F4%29
Check
70=2%28105%2F4%29%2B2%2835%2F4%29
70=%28105%2F2%29%2B%2835%2F2%29
70=%28140%2F2%29
70=70
Correct