Simplify .

Expand using the FOIL Method.

Apply the distributive property.

Apply the distributive property.

Apply the distributive property.

Simplify and combine like terms.

Simplify each term.

Multiply by .

Move to the left of .

Multiply by .

Subtract from .

Subtract from both sides of the equation.

Subtract from .

Use the quadratic formula to find the solutions.

Substitute the values , , and into the quadratic formula and solve for .

Simplify the numerator.

Raise to the power of .

Multiply by .

Multiply by .

Add and .

Rewrite as .

Pull terms out from under the radical, assuming positive real numbers.

Multiply by .

The final answer is the combination of both solutions.

Solve Using the Quadratic Formula (x-2)(x+5)=18