Move to the left side of the equation by subtracting it from both sides.

Rewrite as .

Rewrite as .

Since both terms are perfect squares, factor using the difference of squares formula, where and .

If any individual factor on the left side of the equation is equal to , the entire expression will be equal to .

Set the first factor equal to .

Subtract from both sides of the equation.

Raise each side of the equation to the power to eliminate the fractional exponent on the left side.

Solve the equation for .

Raise to the power of .

Move all terms not containing to the right side of the equation.

Add to both sides of the equation.

Add and .

Set the next factor equal to .

Add to both sides of the equation.

Raise each side of the equation to the power to eliminate the fractional exponent on the left side.

Solve the equation for .

Raise to the power of .

Move all terms not containing to the right side of the equation.

Add to both sides of the equation.

Add and .

The final solution is all the values that make true.

Solve by Factoring (x-4)^(2/3)=81