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