Solve for x
x=4
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31-x+4x-3=40
Add 30 and 1 to get 31.
31+3x-3=40
Combine -x and 4x to get 3x.
28+3x=40
Subtract 3 from 31 to get 28.
3x=40-28
Subtract 28 from both sides.
3x=12
Subtract 28 from 40 to get 12.
x=\frac{12}{3}
Divide both sides by 3.
x=4
Divide 12 by 3 to get 4.
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