The perimeter of a rectangle is 68 inches. The perimeter equals twice the length of L inches, plus twice the width of 9 inches.
P=68
P=2L+2(9)
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Therefore:
2L+2(9)=68
2L+18=68
2L=68-18
2L=50
L=50/2
L=25
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So the length is equal to 25 inches.
p = 68
p = 2l + 2 9
SO
2l + 2 9 = 68
2l + 18 = 68
2l = 68 -18
2l = 50
l = 50 / 2
l = 25