Solve for x
x=2y-21
Solve for y
y=\frac{x+21}{2}
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-x=21-2y
Subtract 2y from both sides.
\frac{-x}{-1}=\frac{21-2y}{-1}
Divide both sides by -1.
x=\frac{21-2y}{-1}
Dividing by -1 undoes the multiplication by -1.
x=2y-21
Divide 21-2y by -1.
2y=21+x
Add x to both sides.
2y=x+21
The equation is in standard form.
\frac{2y}{2}=\frac{x+21}{2}
Divide both sides by 2.
y=\frac{x+21}{2}
Dividing by 2 undoes the multiplication by 2.
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