Solve for x
x=6
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\frac{7}{2}x=21
Combine 3x and \frac{1}{2}x to get \frac{7}{2}x.
x=21\times \frac{2}{7}
Multiply both sides by \frac{2}{7}, the reciprocal of \frac{7}{2}.
x=\frac{21\times 2}{7}
Express 21\times \frac{2}{7} as a single fraction.
x=\frac{42}{7}
Multiply 21 and 2 to get 42.
x=6
Divide 42 by 7 to get 6.
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