Solve for x
x=3
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7x-21=4\left(3-x\right)
Use the distributive property to multiply 7 by x-3.
7x-21=12-4x
Use the distributive property to multiply 4 by 3-x.
7x-21+4x=12
Add 4x to both sides.
11x-21=12
Combine 7x and 4x to get 11x.
11x=12+21
Add 21 to both sides.
11x=33
Add 12 and 21 to get 33.
x=\frac{33}{11}
Divide both sides by 11.
x=3
Divide 33 by 11 to get 3.
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