Solve for x
x = \frac{30}{7} = 4\frac{2}{7} \approx 4.285714286
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6x+15x=90
Combine 5x and x to get 6x.
21x=90
Combine 6x and 15x to get 21x.
x=\frac{90}{21}
Divide both sides by 21.
x=\frac{30}{7}
Reduce the fraction \frac{90}{21} to lowest terms by extracting and canceling out 3.
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