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Find the incorrect step in each solution and explain whit it is incorrect.

Find the incorrect step in each solution and explain whit it is incorrect.-example-1
User Hugh Hou
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1 Answer

14 votes

Answer:

Explanation:

Mai:

She subtracted 5x instead of distributing. This is incorrect, because since it is in ( ), it has to be multiplied by 3.

Correct: 3(5x + 9) = 15x + 27

12x + 3 = 15x + 27

Noah:

Added 15x instead of subtracting. This is incorrect, because to combine like terms on each side you would add a negative number and subtract a positive number.

Correct: 12x + 3 = 15x + 27

12x - 15x = 27 - 3

-3x = 24

x = 24 / -3

x = -8

User ITayb
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