Solve for x
x = \frac{21}{5} = 4\frac{1}{5} = 4.2
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4x+6x=42
Combine x and 3x to get 4x.
10x=42
Combine 4x and 6x to get 10x.
x=\frac{42}{10}
Divide both sides by 10.
x=\frac{21}{5}
Reduce the fraction \frac{42}{10} to lowest terms by extracting and canceling out 2.
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