Simplify the denominator.

Rewrite as .

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

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.

To write as a fraction with a common denominator, multiply by .

To write as a fraction with a common denominator, multiply by .

Multiply and .

Multiply and .

Reorder the factors of .

Combine the numerators over the common denominator.

Apply the distributive property.

Multiply by .

Multiply by .

Apply the distributive property.

Multiply by .

Subtract from .

Simplify x/(x^2-16)-8/(x^2+5x+4)