Solve for x
x=\frac{5}{7}\approx 0.714285714
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4.2x=3
Combine 5.2x and -x to get 4.2x.
x=\frac{3}{4.2}
Divide both sides by 4.2.
x=\frac{30}{42}
Expand \frac{3}{4.2} by multiplying both numerator and the denominator by 10.
x=\frac{5}{7}
Reduce the fraction \frac{30}{42} to lowest terms by extracting and canceling out 6.
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