Graphing

Solving Equations

Using a Graphing Calculator

A graphing calculator can be used to find or check solutions to a system of equations. It can be used as an alternative to graphing the equations by hand. The following example will show graphing using a TI-84 calculator.

Example Solve the following system of equations using a graphing calculator.

Calc ex1

Step 1. Rewrite each equation in slope-intercept form in order to isolate y.

Line 1: Calc_ex1-1

Line 2: Calc_ex1-2

Step 2. Press the [y=] button on the graphing calculator and enter the two functions as:

Calc_ex1-4

Step 3. Now press [GRAPH].

Calc_ex1-5

The window for this graph is set to:

x min: -5
x max: 10
x scl: 1
y min: -5
y max: 5
y scl: 1