Systems, 2 x 2 in this case, are when you have 2 equations and 2 unknowns (letters).
Here's an example:
The goal is to find an x guy and a y guy that work in both equations.
In this chapter, I'll show you three different ways to solve these.
The first method is graphing. This is a cool method to start with since it lets you see what's going on.
We've got two equations -- and they are equations of lines. Let's graph them both on the same axes and see what we get.
Hey, the two lines intersect at
( 2 ,
1 ) .
This means that ( 2 , 1 ) is a point in BOTH lines...
So, x = 2 and y = 1 will work in the equations!
|So, the answer is||.|
Checking your answers, like we did at the end there, is a really good idea... and something you should always do on a test! We're going to do it on every single problem we do!