Solve for x
x=\frac{4y+9}{y-4}
y\neq 4
Solve for y
y=\frac{4x+9}{x-4}
x\neq 4
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xy-4x=4y+9
Subtract 4x from both sides.
\left(y-4\right)x=4y+9
Combine all terms containing x.
\frac{\left(y-4\right)x}{y-4}=\frac{4y+9}{y-4}
Divide both sides by y-4.
x=\frac{4y+9}{y-4}
Dividing by y-4 undoes the multiplication by y-4.
xy-4y=4x+9
Subtract 4y from both sides.
\left(x-4\right)y=4x+9
Combine all terms containing y.
\frac{\left(x-4\right)y}{x-4}=\frac{4x+9}{x-4}
Divide both sides by x-4.
y=\frac{4x+9}{x-4}
Dividing by x-4 undoes the multiplication by x-4.
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Limits
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