This video shows how to simplify fractions within fractions (known as "complex rational expressions). Just find the Lowest Common Denominator (LCD) and multiply all the fractions by it.

This lesson teaches a method for adding and subtracting positive and negative numbers. (Other than the number-line method)

How to add two matrices together. If they both have the same dimensions (same number of rows and columns) then you just add up the numbers that are in the same spot.

This is the last video in a series about systems of linear equations. This lesson looks at how to solve systems by substitution. Isolate (get by itself) one variable and plug the result into the other equation. Plug the answer back into one of the original equations.

Part 3 of a 4 part series on systems of linear equations. This lesson looks at how to solve systems by elimination. Combine both equations together so that one variable cancels out. Then solve for the single variable and plug back into the original equation.

Part 2 of a 4 part series on systems of linear equations. This lesson looks at how to solve systems by graphing. Simply graph both equations on the same coordinate plane and look for the intersection, if it exists.

This lesson is the first of a four part series about systems of linear equations. Here, I define what a system of equations is, and the three types of solutions. Future lessons will cover graphing, elimination, and substitution.

This lessons looks at how to simplify radical expressions which are not perfect squares or cubes. I include an example of square root, cube root, and 4th root. I show a technique to simplify n-root expressions. Also I look at how to simplify variables in radical expressions.