Systems of Linear Equations
Graphing
Graphing
Solving systems with graphing is the
easiest method.
 You must be good at rewriting equations.
 The equations must always be in “y=“
form.

Graphing

Solve the following system by graphing:
◦x+y=4
◦ 3x – 2y = 9
 y=4–x
9
2
 y=− +
 (3.4, 0.6)
3
𝑥
2
1. Rewrite the equations as “y=“
2. Type the equations into the
calculator.
3. Graph.
4. Press 2nd , Trace, 5(intersect).
5. Select the first equation <enter>
6. Select 2nd equation <enter>
7. The calculator says Guess?
<enter>
8. Solution is at the bottom.
Graphing

Try again:
◦ 2x - 3y = 9
◦ 3x + 7y = 1
 y = -3 +
1
7
 y= -
2
x
3
3
x
7
 (2.87, -1.09)
1. Rewrite the equations as
“y=“
2. Type the equations into the
calculator.
3. Graph.
4. Press 2nd , Trace, 5(intersect).
5. Select the first equation
<enter>
6. Select 2nd equation <enter>
7. The calculator says Guess?
<enter>
8. Solution is at the bottom.
Graphing
If there is no solution, the calculator will
give you an error message.
 If there are infinitely many solutions, you
will only see one line on you graph.
 You will just have to pay attention!!

Graphing

Practice makes perfect! Try these:
2x + y = 8
4x – y = 12
x – 2y = 8
4x + 3y = 1
(3.33, 1.33)
(2.36, -2.82)
2x + 2y = 12
4x – 4y = 8
(4,2)