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2. Graph are often used to help visualize the relationship between two
variables. The graph of linear function in two variables is always a
straight line.
A. Slope-intercept Form
If we are given the slope-intercept form y=mx t b, we can use the
value of the slope and y-intercept identified by this equation
form.

3. Example 1. y = 2x - 1
y = 2x – 1
slope: 2
y-intercept: -1

4. Example 2. 5x + 3y = 15
5x + 3y = 15
3y = -5x + 15
3𝑦
3
=
−5𝑥+15
3
3y = -
5𝑥
3
+ 5
slope: -
5
3
y-intercept : 5

5. B. Using x and y-intercept
Another approach in graphing linear functions is by using the
x- and y-intercepts. Since we only need two points to graph a line,
the intercepts will be all that we need and the easiest coordinates to
get. To get the two points, we will substitute the value of x and y to
0.

6. Example 1. 2x – 5y = -6
Let y = 0 Let x = 0
2x – 5y = -6
2x – 5(0) = -6
2x – 0 = -6
2x = -6 + 0
2x = -6
2𝑥
2
=
−6
2
x = -3
Thus, x-intercept is (-3, 0)
2x – 5y = -6
2(0) – 5y = -6
0 – 5y = -6
-5y = -6 – 0
-5y = -6
−5𝑦
−5
=
−6
−5
y =
6
5
Thus, y-intercept is (0,
6
5
)

7. Example 2. 3x + 2y = 12
Let y = 0 Let x = 0
3x + 2y = 12
3x + 2(0) = 12
3x + 0 = 12
3x = 12 – 0
3x = 12
x =
12
3
x = 4
Thus, x-intercept is (4,0)
3x + 2y = 12
3(0) + 2y = 12
0 + 2y = 12
2y = 12 – 0
2y = 12
y =
12
2
y = 6
Thus, y-intercept is (0, 6)