4.3
Graphing with
Intercepts
find the x- and y-intercepts of
linear equations.
What does it mean to INTERCEPT a
pass in football?
The path of the defender crosses
the path of the thrown football.
In algebra, what are x- & y-intercepts?
What are the x- and y-intercepts?
The x-intercept is
where the graph
crosses the x-axis.
To find the xintercept let y=0
and solve for x.
The y-intercept is
where the graph
crosses the y-axis.
To find the yintercept let x=0
and solve for y.
(2, 0)
(0, -6)
What do all x-intercepts have
in common?
1.
2.
3.
25%
75%
0%
They have the same
x coordinate
They have the same
y coordinate
They have nothing in
common
x-intercept: Let y=0
2x +3(0) = 6
2x = 6
x=3; (3, 0)
y-intercept: Let x=0
2(0) +3y = 6
3y = 6
y=2; (0, 2)
2x +3y = 6
x-intercept: Let y=0
-2x +4(0) = -16
-2x = -16
x=8; (8, 0)
y-intercept: Let x=0
-2(0) +4y = -16
4y = -16
y=-4; (0, -4)
-2x +4y = -16
x-intercept: Let y=0
3x -4(0) = 24
3x = 24
x=8; (8, 0)
y -intercept: Let x=0
3(0) -4y = 24
-4y = 24
y=-6; (0, -6)
3x -4y = 24
Find the x- and y-intercepts.
y=7
x-intercept:
There is no x-intercept. None
y-intercept:
(0,7)
What type of lines have no x-intercept?
What type of lines have no y-intercept?
Remember
When finding the
x-intercept, let y=0.
When finding the
y-intercept, let x=0