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Find the error then show the correct way step by step.

Find the error then show the correct way step by step.-example-1
User Alexander Blyth
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1 Answer

21 votes
21 votes

Question 4

The error was that in step 2, when distributing -3 into the parentheses, the person did not change the sign of 24 so that it was negative, since a negative number multiplied by a positive number will always make a negative number. Here is the correct way to solve this equation:


-5x+12-7x=-3(5x+8)\\-12x+12=-3(5x+8)

Distrubute -3 into the parentheses


-12x+12=-15x-24

Subtract both sides by 12


-12x+12-12=-15x-24-12\\-12=-15x-36

Add 15x to both sides


-12+15x=-15x-36+15x\\3x=-36

Divide both sides by 3


(3x)/(3) =(-36)/(3) \\x=-12

Question 5

The error was that 2 was added on both sides in step 5 instead of being subtracted from both sides. Here is the correct way to do it, starting from step 4:


10=16x+2

Subtract both sides by 2


10-2=16x+2-2\\8=16x

Divide both sides by 16


(8)/(16) =(16x)/(16) \\(1)/(2)=x

I hope this helps!

User Joe Laviano
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2.9k points
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