Solve for x
x=\frac{7\left(y+3\right)}{9}
Solve for y
y=\frac{9x}{7}-3
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9x=7y+21
The equation is in standard form.
\frac{9x}{9}=\frac{7y+21}{9}
Divide both sides by 9.
x=\frac{7y+21}{9}
Dividing by 9 undoes the multiplication by 9.
x=\frac{7y}{9}+\frac{7}{3}
Divide 21+7y by 9.
7y+21=9x
Swap sides so that all variable terms are on the left hand side.
7y=9x-21
Subtract 21 from both sides.
\frac{7y}{7}=\frac{9x-21}{7}
Divide both sides by 7.
y=\frac{9x-21}{7}
Dividing by 7 undoes the multiplication by 7.
y=\frac{9x}{7}-3
Divide 9x-21 by 7.
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