Solve for x
x=8
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3x+21-15=30
Use the distributive property to multiply x+7 by 3.
3x+6=30
Subtract 15 from 21 to get 6.
3x=30-6
Subtract 6 from both sides.
3x=24
Subtract 6 from 30 to get 24.
x=\frac{24}{3}
Divide both sides by 3.
x=8
Divide 24 by 3 to get 8.
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