Solve for u square root of u-7=5

$\sqrt{u - 7} = 5$

Step 1

To remove the radical on the left side of the equation, square both sides of the equation.

${\sqrt{u - 7}}^{2} = 5^{2}$

Step 2

Simplify each side of the equation.

Use $\sqrt[n]{a^{x}} = a^{\frac{x}{n}}$ to rewrite $\sqrt{u - 7}$ as ${(u - 7)}^{\frac{1}{2}}$ .

${({(u - 7)}^{\frac{1}{2}})}^{2} = 5^{2}$

Simplify the left side.

Simplify ${({(u - 7)}^{\frac{1}{2}})}^{2}$ .

Multiply the exponents in ${({(u - 7)}^{\frac{1}{2}})}^{2}$ .

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

${(u - 7)}^{\frac{1}{2} \cdot 2} = 5^{2}$

Cancel the common factor of $2$ .

Cancel the common factor.

${(u - 7)}^{\frac{1}{2} \cdot 2} = 5^{2}$

Rewrite the expression.

${(u - 7)}^{1} = 5^{2}$

Simplify.

$u - 7 = 5^{2}$

Simplify the right side.

Raise $5$ to the power of $2$ .

$u - 7 = 25$

Step 3

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

Add $7$ to both sides of the equation.

$u = 25 + 7$

Add $25$ and $7$ .

$u = 32$