Solve for x
x=\frac{21-3y}{8}
Solve for y
y=-\frac{8x}{3}+7
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8x-21=-3y
Subtract 3y from both sides. Anything subtracted from zero gives its negation.
8x=-3y+21
Add 21 to both sides.
8x=21-3y
The equation is in standard form.
\frac{8x}{8}=\frac{21-3y}{8}
Divide both sides by 8.
x=\frac{21-3y}{8}
Dividing by 8 undoes the multiplication by 8.
3y-21=-8x
Subtract 8x from both sides. Anything subtracted from zero gives its negation.
3y=-8x+21
Add 21 to both sides.
3y=21-8x
The equation is in standard form.
\frac{3y}{3}=\frac{21-8x}{3}
Divide both sides by 3.
y=\frac{21-8x}{3}
Dividing by 3 undoes the multiplication by 3.
y=-\frac{8x}{3}+7
Divide -8x+21 by 3.
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