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Question from Megan, a student:

6(x-1)-3(x+1)-12=56+5x

Hi Megan,

Lets try this one

5(x + 2) - 7 = 3(x - 1) + 4x

First you need to expand the terms 5(x + 2) and 3(x - 1) using the distributive law

5(x + 2) - 7 = 3(x - 1) + 4x
5x + 5 × 2 - 7 = 3x - 3 × 1 + 4x
5x + 10 - 7 = 3x - 3 + 4x

Then collect terms on each side

5x + 10 - 7 = 3x - 3 + 4x
5x + 3 = 7x - 3

At this point I would subtract 5x from each side so that the "x terms" are all on one side

5x + 3 = 7x - 3
5x + 3 - 5x = 7x - 3 - 5x
3 = 2x - 3

Now add 3 to each side to eliminate the -3 term from the right side

3 = 2x - 3
3 + 3 = 2x - 3 + 3
6 = 2x

Thus

x = 3.

Now try your problem,
Penny

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