Solve for x
x = \frac{15}{2} = 7\frac{1}{2} = 7.5
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3x+x=30
Multiply both sides of the equation by 15, the least common multiple of 5,15.
4x=30
Combine 3x and x to get 4x.
x=\frac{30}{4}
Divide both sides by 4.
x=\frac{15}{2}
Reduce the fraction \frac{30}{4} to lowest terms by extracting and canceling out 2.
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