Dead Bunny Educational

March 12, 2007

Solving a system of equations by graphing

Filed under: Math Tidbits — Rebecca @ 12:28 pm

Sometimes, you need to know what points on a graph make two or more equations true. This is called solving a system of equations. There are a few ways you can do this.

The first is to graph the lines and see where they meet.

Let’s look at the graph of y= -3 and y=x. We graph both on the same graph and get this:Solution of two lines graphed

We look at the graph to visually tell where they intersect. In this case, they meet up right around (-3, -3). So the solution for this set of equations is (-3, -3) because it’s the only point that is on both lines.

Some students find this the simplest method for solving a system of equations. Others find this method a good way to double check their answer when they solve a system using a different method.

The other methods, solving by substitution or by elimination, will be covered later this week.

3 Comments »

  1. [...] Solving a system of equations by graphing [...]

    Pingback by Today was about quantum « Kirylin’s Notebook — March 12, 2007 @ 10:48 pm | Reply

  2. [...] Filed under: Math Tidbits — kirylin @ 12:43 pm The other day, we talked about solving a system of equations by graphing. Today, we’re going to look at solving a system of equations by [...]

    Pingback by Solving a system of equations by substitution « Dead Bunny Educational — March 13, 2007 @ 1:08 pm | Reply

  3. [...] under: Math Tidbits — kirylin @ 1:04 pm So far, we’ve solved a system of equations by graphing and by substitution. Today, we tackle the challenging method of solving a system of equations by [...]

    Pingback by Solving a system of equations by elimination « Dead Bunny Educational — March 15, 2007 @ 2:05 pm | Reply


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