Solve for x
x=\frac{5\left(y+4\right)}{4}
Solve for y
y=\frac{4\left(x-5\right)}{5}
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4x=20+5y
Add 5y to both sides.
4x=5y+20
The equation is in standard form.
\frac{4x}{4}=\frac{5y+20}{4}
Divide both sides by 4.
x=\frac{5y+20}{4}
Dividing by 4 undoes the multiplication by 4.
x=\frac{5y}{4}+5
Divide 20+5y by 4.
-5y=20-4x
Subtract 4x from both sides.
\frac{-5y}{-5}=\frac{20-4x}{-5}
Divide both sides by -5.
y=\frac{20-4x}{-5}
Dividing by -5 undoes the multiplication by -5.
y=\frac{4x}{5}-4
Divide 20-4x by -5.
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