Solve for x
x=7
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3x-9+2\left(2x+1\right)=42
Use the distributive property to multiply 3 by x-3.
3x-9+4x+2=42
Use the distributive property to multiply 2 by 2x+1.
7x-9+2=42
Combine 3x and 4x to get 7x.
7x-7=42
Add -9 and 2 to get -7.
7x=42+7
Add 7 to both sides.
7x=49
Add 42 and 7 to get 49.
x=\frac{49}{7}
Divide both sides by 7.
x=7
Divide 49 by 7 to get 7.
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