Answer: 63 meters
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Work Shown:
width = w
length = w+9
perimeter = 2*(length + width)
P = 2(w+9+w)
P = 2(2w+9)
P = 4w+18
4w+18 = P
4w+18 = 270
4w = 270 - 18
4w = 252
w = 252/4
w = 63 meters is the width
w+9 = 63+9 = 72 meters is the length
Check:
perimeter = 2*(length + width)
perimeter = 2*(72 + 63)
perimeter = 2*(135)
perimeter = 270
The answer is confirmed.