6.1 Systems of Linear Equations (2 variables)

We introduce two approaches to solving system of linear equations of two variables. The first is substitution. Here we solve for one variable in one equation, say y, and then substitute the expression equivalent to y into the other equation. This leaves an equation that only has x-es in it, which can be solved using the techniques we learned in chapter one. Once we know what x is, we can use the first equation to solve for the matching y.

Here is a worksheet of systems of equations you can do using the substitution method.

The second method is called elimination. Here we multiply one or more of the equations by numbers, so that when added, one of the variables goes away. This leaves an equation with only one variable, as in the previous method.

Here is a worksheet to practice solving system of equations with two variables by elimination.