The Coordinate Plane
Algebra I Glencoe
Mathematics 2004
The McGraw Hill
Companies Inc.
Vocabulary Words
Axes - two perpendicular number lines
used for locating points
Origin – the intersection of the two axes
Y-axis – the vertical number line
X-axis – the hoizontal number line
The four quadrants of the coordinate plane.
Y-axis
Quadrant
II
Quadrant
I
X-axis
Quadrant
III
Quadrant
IV
Signs of the quadrants.
Y-axis
(-,+)
(+,+)
X-axis
(-,-)
(+,-)
The Ordered Pair
(5,10)
X-
Y-
coordinate
coordinate
The Origin Point
Y-axis
Origin
Point
(0,0)
X-axis
•Always start at
the origin to
plot a point.
Direction of Movement for the X-Coordinate
Y-axis
If the x-
coordinate
is negative
move this
way
If the x-
coordinate
is positive
move this
way
X-axis
Direction of movement for the Y-coordinate
Y-axis
If the y-
coordinate
is negative
move this
way
If the y-
coordinate
is positive
move this
way
X-axis
Name the given point.
Y-axis
(-2,1)
(1,3)
X-axis
(-5,-1)
(4,0)
How To Plot a Point on the Coordinate Plane
Y-axis
(4,4)
Next move
on the Yaxis
X-axis
(-3,-1)
First move
out on the
X-axis