Solve for x
x=\frac{2\left(y-21\right)}{9}
Solve for y
y=\frac{9x}{2}+21
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\frac{9}{2}x+21=y
Swap sides so that all variable terms are on the left hand side.
\frac{9}{2}x=y-21
Subtract 21 from both sides.
\frac{\frac{9}{2}x}{\frac{9}{2}}=\frac{y-21}{\frac{9}{2}}
Divide both sides of the equation by \frac{9}{2}, which is the same as multiplying both sides by the reciprocal of the fraction.
x=\frac{y-21}{\frac{9}{2}}
Dividing by \frac{9}{2} undoes the multiplication by \frac{9}{2}.
x=\frac{2y}{9}-\frac{14}{3}
Divide y-21 by \frac{9}{2} by multiplying y-21 by the reciprocal of \frac{9}{2}.
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