Solve for x
x=-\frac{5y}{4}+\frac{21}{2}
Solve for y
y=\frac{42-4x}{5}
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4x=42-5y
Subtract 5y from both sides.
\frac{4x}{4}=\frac{42-5y}{4}
Divide both sides by 4.
x=\frac{42-5y}{4}
Dividing by 4 undoes the multiplication by 4.
x=-\frac{5y}{4}+\frac{21}{2}
Divide 42-5y by 4.
5y=42-4x
Subtract 4x from both sides.
\frac{5y}{5}=\frac{42-4x}{5}
Divide both sides by 5.
y=\frac{42-4x}{5}
Dividing by 5 undoes the multiplication by 5.
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