Question

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Answer 1

Answer:

$\large \boxed{\sf \ \ 64 \ \ }$

Step-by-step explanation:

Hello,

$2(a+b+c)=(a+b)+(b+c)+(c+a)=4+5+7=16\\\\\text{*** divide by 2 both sides ***}\\\\(a+b+c)=\dfrac{16}{2}=8 \ \ \text{ so...}\\\\(a+b+c)^2=8^2=\large \boxed{64}$

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