Solve by Factoring (x+2)^(2/3)=9

${(x + 2)}^{\frac{2}{3}} = 9$

Step 1

Subtract $9$ from both sides of the equation.

${(x + 2)}^{\frac{2}{3}} - 9 = 0$

Step 2

Rewrite ${(x + 2)}^{\frac{2}{3}}$ as ${({(x + 2)}^{\frac{1}{3}})}^{2}$ .

${({(x + 2)}^{\frac{1}{3}})}^{2} - 9 = 0$

Step 3

Rewrite $9$ as $3^{2}$ .

${({(x + 2)}^{\frac{1}{3}})}^{2} - 3^{2} = 0$

Step 4

Since both terms are perfect squares, factor using the difference of squares formula, $a^{2} - b^{2} = (a + b) (a - b)$ where $a = {(x + 2)}^{\frac{1}{3}}$ and $b = 3$ .

$({(x + 2)}^{\frac{1}{3}} + 3) ({(x + 2)}^{\frac{1}{3}} - 3) = 0$

Step 5

If any individual factor on the left side of the equation is equal to $0$ , the entire expression will be equal to $0$ .

${(x + 2)}^{\frac{1}{3}} + 3 = 0$

${(x + 2)}^{\frac{1}{3}} - 3 = 0$

Step 6

Set ${(x + 2)}^{\frac{1}{3}} + 3$ equal to $0$ and solve for $x$ .

Set ${(x + 2)}^{\frac{1}{3}} + 3$ equal to $0$ .

${(x + 2)}^{\frac{1}{3}} + 3 = 0$

Solve ${(x + 2)}^{\frac{1}{3}} + 3 = 0$ for $x$ .

Subtract $3$ from both sides of the equation.

${(x + 2)}^{\frac{1}{3}} = - 3$

Raise each side of the equation to the power of $3$ to eliminate the fractional exponent on the left side.

${({(x + 2)}^{\frac{1}{3}})}^{3} = {(- 3)}^{3}$

Simplify the exponent.

Simplify the left side.

Simplify ${({(x + 2)}^{\frac{1}{3}})}^{3}$ .

Multiply the exponents in ${({(x + 2)}^{\frac{1}{3}})}^{3}$ .

Apply the power rule and multiply exponents, ${(a^{m})}^{n} = a^{m n}$ .

${(x + 2)}^{\frac{1}{3} \cdot 3} = {(- 3)}^{3}$

Cancel the common factor of $3$ .

Cancel the common factor.

${(x + 2)}^{\frac{1}{3} \cdot 3} = {(- 3)}^{3}$

Rewrite the expression.

${(x + 2)}^{1} = {(- 3)}^{3}$

Simplify.

$x + 2 = {(- 3)}^{3}$

Simplify the right side.

Raise $- 3$ to the power of $3$ .

$x + 2 = - 27$

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

Subtract $2$ from both sides of the equation.

$x = - 27 - 2$

Subtract $2$ from $- 27$ .

$x = - 29$

Step 7

Set ${(x + 2)}^{\frac{1}{3}} - 3$ equal to $0$ and solve for $x$ .

Set ${(x + 2)}^{\frac{1}{3}} - 3$ equal to $0$ .

${(x + 2)}^{\frac{1}{3}} - 3 = 0$

Solve ${(x + 2)}^{\frac{1}{3}} - 3 = 0$ for $x$ .

Add $3$ to both sides of the equation.

${(x + 2)}^{\frac{1}{3}} = 3$

Raise each side of the equation to the power of $3$ to eliminate the fractional exponent on the left side.

${({(x + 2)}^{\frac{1}{3}})}^{3} = 3^{3}$

Simplify the exponent.

Simplify the left side.

Simplify ${({(x + 2)}^{\frac{1}{3}})}^{3}$ .

Multiply the exponents in ${({(x + 2)}^{\frac{1}{3}})}^{3}$ .

Apply the power rule and multiply exponents, ${(a^{m})}^{n} = a^{m n}$ .

${(x + 2)}^{\frac{1}{3} \cdot 3} = 3^{3}$

Cancel the common factor of $3$ .

Cancel the common factor.

${(x + 2)}^{\frac{1}{3} \cdot 3} = 3^{3}$

Rewrite the expression.

${(x + 2)}^{1} = 3^{3}$

Simplify.

$x + 2 = 3^{3}$

Simplify the right side.

Raise $3$ to the power of $3$ .

$x + 2 = 27$

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

Subtract $2$ from both sides of the equation.

$x = 27 - 2$

Subtract $2$ from $27$ .

$x = 25$

Step 8

The final solution is all the values that make $({(x + 2)}^{\frac{1}{3}} + 3) ({(x + 2)}^{\frac{1}{3}} - 3) = 0$ true.

$x = - 29, 25$

Solve by Factoring (x+2)^(2/3)=9

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