Use Multiplication Distributive Property: \({(xy)}^{a}={x}^{a}{y}^{a}\).
\[{5}^{2}{\sqrt{a+8x}}^{2}={(25+4x)}^{2}\]
Simplify \({5}^{2}\) to \(25\).
\[25{\sqrt{a+8x}}^{2}={(25+4x)}^{2}\]
Use this rule: \({\sqrt{x}}^{2}=x\).
\[25(a+8x)={(25+4x)}^{2}\]
Divide both sides by \(25\).
\[a+8x=\frac{{(25+4x)}^{2}}{25}\]
Subtract \(8x\) from both sides.
\[a=\frac{{(25+4x)}^{2}}{25}-8x\]
a=(25+4*x)^2/25-8*x
