Topics covered:

- Linear equations and functions

https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:linear-equations-graphs

 

- Linear systems and matrices

https://www.khanacademy.org/math/algebra-home/alg-system-of-equations/alg-equivalent-systems-of-equations/v/solving-systems-of-equations-by-elimination

 

- Quadratic equations and functions

https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:quadratic-functions-equations

 

- Polynomial expressions and equations

https://www.khanacademy.org/math/algebra-home/alg-polynomials

 

- Rational exponents

https://www.khanacademy.org/math/algebra2/x2ec2f6f830c9fb89:exp

 

- Radical functions

https://www.khanacademy.org/math/algebra-home/alg-exp-and-log/alg-simplify-higher-index-roots/v/radical-expressions-with-higher-roots

 

- Exponential functions (scroll down a lot)

https://www.khanacademy.org/math/algebra-home/alg-exp-and-log

 

- Logarithmic functions (scroll down even more!)

https://www.khanacademy.org/math/algebra-home/alg-exp-and-log

 

- Trigonometry

https://www.khanacademy.org/math/trigonometry

 

- Probability

https://www.khanacademy.org/math/statistics-probability/probability-library