Simplify \(4\times \frac{x}{5}\) to \(\frac{4x}{5}\).
\[\frac{4x}{5}+10=90\]
Subtract \(10\) from both sides.
\[\frac{4x}{5}=90-10\]
Simplify \(90-10\) to \(80\).
\[\frac{4x}{5}=80\]
Multiply both sides by \(5\).
\[4x=80\times 5\]
Simplify \(80\times 5\) to \(400\).
\[4x=400\]
Divide both sides by \(4\).
\[x=\frac{400}{4}\]
Simplify \(\frac{400}{4}\) to \(100\).
\[x=100\]
x=100
