Solve for x
x=80
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3x+2x+4x=720
Multiply both sides of the equation by 4, the least common multiple of 4,2.
5x+4x=720
Combine 3x and 2x to get 5x.
9x=720
Combine 5x and 4x to get 9x.
x=\frac{720}{9}
Divide both sides by 9.
x=80
Divide 720 by 9 to get 80.
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