Solve for x
x=12
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4x+3x=84
Multiply both sides of the equation by 12, the least common multiple of 3,4.
7x=84
Combine 4x and 3x to get 7x.
x=\frac{84}{7}
Divide both sides by 7.
x=12
Divide 84 by 7 to get 12.
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