<PRE><B>Question 335315</B>
The formula for finding out the perimeter of a rectangle is 2L+2w= perimeter
In this problem we are told that the perimiter is = to 60 and that the length is 3 times as long as the width. So L =2(3w) 
 your  equation is 2(3w)+2w=60
 use distribution to solve the 2(3w) and get 6w+2w=60
combine like terms                           8w=60
divide both sides by 8 to get w alone 8w divided by 8 is w and 60 divided by 8 is 7.5 so w= 7.5

now that you know w is = to 7.5 and you know that the lenth is 3 times long you mulitply 7.5 by three and get 22.5
w=7.5
L=22.5

to check plug the numbers back in 2(7.5) + 2(22.5) = 60?  15+ 45 = 60 since it checks its correct.
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