Question 1016667
The perimeter in this case is:
2L+2W = 840
and the problem says that:
L = 3W-60 Substitute for L in the formula above:
2(3W-60)+2W = 840
6W-120+2W= 840 Add 120 on both sides and add W on left:
8W = 960 Divide both sides by 8
W = 120 And the length L is:
L= 3W-60; L = 120(3)-60= 300
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Check:
2(300)+2(120)= 840
600+240 = 840 We have the correct answer.
J