19) 7x - 8(-x+7)=-16+ 7x Can someone help me solve this problem and also tell me what type of problem this is ?

Hi there!  

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I believe your answer is:  

x = 5

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Here’s why:  

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Hope this helps you. I apologize if it’s incorrect.  

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6