Solve for x
x=4
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7x+13-5x=21
Subtract 5x from both sides.
2x+13=21
Combine 7x and -5x to get 2x.
2x=21-13
Subtract 13 from both sides.
2x=8
Subtract 13 from 21 to get 8.
x=\frac{8}{2}
Divide both sides by 2.
x=4
Divide 8 by 2 to get 4.
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