Solve for x
x=\frac{21-7y}{5}
Solve for y
y=-\frac{5x}{7}+3
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5x=21-7y
Subtract 7y from both sides.
\frac{5x}{5}=\frac{21-7y}{5}
Divide both sides by 5.
x=\frac{21-7y}{5}
Dividing by 5 undoes the multiplication by 5.
7y=21-5x
Subtract 5x from both sides.
\frac{7y}{7}=\frac{21-5x}{7}
Divide both sides by 7.
y=\frac{21-5x}{7}
Dividing by 7 undoes the multiplication by 7.
y=-\frac{5x}{7}+3
Divide 21-5x by 7.
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