2.3
Horizontal and
Vertical Lines
Objectives:
- To graph horizontal and vertical lines
- To write equations of horizontal and vertical lines
Horizontal Line - a line that runs from ___________ to
____________.
Vertical Line - a line that runs ___________ and
___________.
Plot the three points. Then connect the three points.
x
Do you notice anything?
What kind of a line is connecting them?
y
3
-5
3
1
3
6
What do each of the points have in common?
What axis is the line going through?
Vertical Lines
* Equation looks like:
*All of the ______ coordinates are the same as _____________ in the equation.
* The line goes through the ___________ at the number that is in the equation.
* The axis that the vertical line goes through is actually _______________. (think
opposites)
EXAMPLE:
Graph:
Plot the three points. Then connect the three points.
x
Do you notice anything?
What kind of a line is connecting them?
y
-3
5
1
5
8
5
What do each of the points have in common?
What axis is the line going through?
Horizontal Lines
* Equation looks like:
*All of the ______ coordinates are the same as _____________ in the equation.
* The line goes through the ___________ at the number that is in the equation.
* The axis that the horizontal line goes through is actually _______________. (think
opposites)
EXAMPLE:
Graph:
Graph the following lines in different colors. Mark the color that
each line is graphed in next to the equation of the line so it is easy
to study these examples!
x = -4
y = -1
y=3
x=7
y = -6
x=2