Evaluate square root of 3x+7=x-1

$\sqrt{3 x + 7} = x - 1$

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

${\sqrt{3 x + 7}}^{2} = {(x - 1)}^{2}$

Simplify each side of the equation.

Use $\sqrt[n]{a^{x}} = a^{\frac{x}{n}}$ to rewrite $\sqrt{3 x + 7}$ as ${(3 x + 7)}^{\frac{1}{2}}$ .

${({(3 x + 7)}^{\frac{1}{2}})}^{2} = {(x - 1)}^{2}$

Simplify the left side.

Simplify ${({(3 x + 7)}^{\frac{1}{2}})}^{2}$ .

Multiply the exponents in ${({(3 x + 7)}^{\frac{1}{2}})}^{2}$ .

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

${(3 x + 7)}^{\frac{1}{2} \cdot 2} = {(x - 1)}^{2}$

Cancel the common factor of $2$ .

Cancel the common factor.

${(3 x + 7)}^{\frac{1}{2} \cdot 2} = {(x - 1)}^{2}$

Rewrite the expression.

${(3 x + 7)}^{1} = {(x - 1)}^{2}$

Simplify.

$3 x + 7 = {(x - 1)}^{2}$

Simplify the right side.

Simplify ${(x - 1)}^{2}$ .

Rewrite ${(x - 1)}^{2}$ as $(x - 1) (x - 1)$ .

$3 x + 7 = (x - 1) (x - 1)$

Expand $(x - 1) (x - 1)$ using the FOIL Method.

Apply the distributive property.

$3 x + 7 = x (x - 1) - 1 (x - 1)$

Apply the distributive property.

$3 x + 7 = x \cdot x + x \cdot - 1 - 1 (x - 1)$

Apply the distributive property.

$3 x + 7 = x \cdot x + x \cdot - 1 - 1 x - 1 \cdot - 1$

Simplify and combine like terms.

Simplify each term.

Multiply $x$ by $x$ .

$3 x + 7 = x^{2} + x \cdot - 1 - 1 x - 1 \cdot - 1$

Move $- 1$ to the left of $x$ .

$3 x + 7 = x^{2} - 1 \cdot x - 1 x - 1 \cdot - 1$

Rewrite $- 1 x$ as $- x$ .

$3 x + 7 = x^{2} - x - 1 x - 1 \cdot - 1$

Rewrite $- 1 x$ as $- x$ .

$3 x + 7 = x^{2} - x - x - 1 \cdot - 1$

Multiply $- 1$ by $- 1$ .

$3 x + 7 = x^{2} - x - x + 1$

Subtract $x$ from $- x$ .

$3 x + 7 = x^{2} - 2 x + 1$

Solve for $x$ .

Since $x$ is on the right side of the equation, switch the sides so it is on the left side of the equation.

$x^{2} - 2 x + 1 = 3 x + 7$

Move all terms containing $x$ to the left side of the equation.

Subtract $3 x$ from both sides of the equation.

$x^{2} - 2 x + 1 - 3 x = 7$

Subtract $3 x$ from $- 2 x$ .

$x^{2} - 5 x + 1 = 7$

Subtract $7$ from both sides of the equation.

$x^{2} - 5 x + 1 - 7 = 0$

Subtract $7$ from $1$ .

$x^{2} - 5 x - 6 = 0$

Factor $x^{2} - 5 x - 6$ using the AC method.

Consider the form $x^{2} + b x + c$ . Find a pair of integers whose product is $c$ and whose sum is $b$ . In this case, whose product is $- 6$ and whose sum is $- 5$ .

$- 6, 1$

Write the factored form using these integers.

$(x - 6) (x + 1) = 0$

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

$x - 6 = 0$

$x + 1 = 0$

Set $x - 6$ equal to $0$ and solve for $x$ .

Set $x - 6$ equal to $0$ .

$x - 6 = 0$

Add $6$ to both sides of the equation.

$x = 6$

Set $x + 1$ equal to $0$ and solve for $x$ .

Set $x + 1$ equal to $0$ .

$x + 1 = 0$

Subtract $1$ from both sides of the equation.

$x = - 1$

The final solution is all the values that make $(x - 6) (x + 1) = 0$ true.

$x = 6, - 1$

Exclude the solutions that do not make $\sqrt{3 x + 7} = x - 1$ true.

$x = 6$

Evaluate square root of 3x+7=x-1

Related Questions

Support LCMGCF.com by disabling your adblocker.