PLease help me out will give u brainiest
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Answer: 252 ft
Step-by-step explanation:
Perimeter is 2(l + w), so when length and width are scaled by 3.5 the new perimeter is 2(3.5l + 3.5w), when factored is 7(l+w). since we are multiplying both sides by 3.5, we multiply 72 by 3.5 to get 252.