Factoring Polynomials

I work through 6 Khan Academy exercises on factoring. They are as follows.
1. Khan Academy: Identify Quadratic Patterns
2. Khan Academy: Factorization with Substitution
3. Khan Academy: Factor Polynomials Using Structure.
4. Khan Academy: Factor Higher Degree Polynomials
5. Khan Academy: Polynomial Special Products: Difference of Squares
6. Khan Academy: Polynomial Special Products: Perfect Square Trinomials