Set equal to .

Factor the left side of the equation.

Regroup terms.

Factor out of .

Factor out of .

Factor out of .

Factor out of .

Rewrite as .

Factor.

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

Remove unnecessary parentheses.

Rewrite as .

Let . Substitute for all occurrences of .

Factor using the AC method.

Consider the form . Find a pair of integers whose product is and whose sum is . In this case, whose product is and whose sum is .

Write the factored form using these integers.

Replace all occurrences of with .

Rewrite as .

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

Factor out of .

Factor out of .

Factor out of .

Reorder terms.

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 and solve.

Set the first factor equal to .

Subtract from both sides of the equation.

Set the next factor equal to and solve.

Set the next factor equal to .

Add to both sides of the equation.

Set the next factor equal to and solve.

Set the next factor equal to .

Use the quadratic formula to find the solutions.

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

Simplify.

Simplify the numerator.

One to any power is one.

Multiply by .

Multiply by .

Subtract from .

Rewrite as .

Rewrite as .

Rewrite as .

Multiply by .

The final answer is the combination of both solutions.

The final solution is all the values that make true.

Find the Roots (Zeros) x^4+x^3-15x^2-16x-16