Question

What is the answer to the equation 5+2(x-1)=12

Answer 1

5+2(x-1)= 12
So you need to get rid of parentheses, which is that you have to distribute.
5+2x-2= 12
-5             -5    (Inverse)
2x-2= 7
    +2  +2         (Another inverse)
2x= 9
2      2       (Divide)

x= 4.5
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Check
5+2(4.5-1)=12
5+2(3.5)=12
5+7=12
12=12

Answer 2

$5+2(x-1)=12 \\ \\ 2 ( x - 1) = 12 - 5 \ / \ subtract \ 5 \ from \ each \ side \\ \\ 2(x - 1) = 7 \ / \ simplify \\ \\ x - 1 = \frac{7}{2} \ / \ divide \ each \ side \ by \ 2 \\ \\ x = \frac{7}{2} + 1 \ / \ add \ 1 \ to \ each \ side \\ \\ x = \frac{9}{2} \ / \ simplify$

So, the answer to this problem is x = 9/2 or x = 4.5.