Rewrite as .

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

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

Multiply and .

Combine the numerators over the common denominator.

Factor out of .

Factor out of .

Factor out of .

Factor out of .

Apply the distributive property.

Multiply by .

Subtract from .

Cancel the common factor.

Rewrite the expression.

Simplify (6n)/(n^2-9)-3/(n+3)