A lesson on graphing linear equations appropriate for middle and high school Algebra or Pre-Algebra students.

2. Linear Equation: an equation whose
graph forms a line.
1143 =− yx
262
+−= xxy
is linear.
is not.
In linear equations, all variables are
taken to the first power.
Linear means of a
line. So a linear equation is the equation
of a line.
Why?

3. Suppose you were asked to graph the
solution set of the linear equation,
.3=+ yx
You could start by creating a table of
values.
x
y

4. Choose any number to use as x or y . . .
3=+ yx
x
y
0

5. 3=+ y
. . . and substitute the number for the
variable.
3
0x
3=y
x
y
0
Then calculate to find,

6. 3=+ y
Continue, until you have 3 sets of x and
y values.
3
3x
x
y
0 3
0

7. 3=+x
Continue, until you have 3 sets of x and
y values.
3
x
y
0 3
0
y
6
3−
6

8. With your table completed for three sets
of values, you are ready to graph the
line.
3
x
y
0 3
0 6
3−
3=+ yx

9. When x is 0, y is 3, so plot the point,
(0, 3).
3
x
y
0 3
0 6
3−
3=+ yx ( )3,0

10. And when x is 3, y is 0, so plot the
point, (3, 0).
3
x
y
0 3
0 6
3−
3=+ yx
( )0,3

11. And finally, when x is -3, y is 6, so
plot the point, (-3, 6).
3
x
y
0 3
0 6
3−
3=+ yx ( )6,3−

12. If the three points do not line up, you
need to find your mistake.
3
x
y
0 3
0 6
3−
3=+ yx
If they do line up, you just need to
connect the dots.

13. This is the graph of the linear equation,
.3=+ yx

14. Create a table of values for each
equation, and graph it on grid paper:
1.
2.
3.
5−=− yx
72 =+ yx
42 −= xy
4. 1
2
1
+= xy