Transcript 1.1 The Cartesian Plane

Chapter 1
1.1 The Cartesian Plane
Ms. Robin
You will learn:
• To label the axes and origin of a Cartesian plane
• Identify and plot points on a Cartesian plane
Terms:
1. Cartesian Plane – The plane formed when a horizontal number line
and a vertical number line cross. Also called a coordinate grid.
2. X – Axis: the horizontal number line on the coordinate grid.
3. Y-Axis: the vertical number line on the coordinate grid.
4. Origin: the point where the x-axis and the y-axis cross.
5. Quadrants: the four regions on the coordinate grid.
6. Ordered Pair: a pair of numbers used to locate a point on a
coordinate grid.
7. Coordinates: the values in an ordered pair (x, y)
Ex. (4,5) (3,2) (0,0) (7,2)
The Cartesian Plane
How To Read Coordinates
• Read the x-coordinate first, then the y-coordinate  (x, y)
Ex. (1,5) “The ordered pair one, five.”
(7, -3) “The ordered pair seven, negative three.”
• The first number (x-value) tells us how far to the right or left
we move.
Ex. (4, y) Move 4 units to the right.
(-6, y) Move 6 units left.
• The second number (y-value) tells us how far to move up or
down.
Ex. (x, 3) Move 3 units up.
(x, -7) Move 7 units down.
How To Write Coordinates
Follow the following steps:
1. Determine the x-coordinate
2. Determine the y-coordinate
3. Write in form (x, y)
Example 1: Identify the Points on the Grid
A ________
B ________
C ________
D ________
E ________
F ________
Example 2: Plot the Points on a Grid
Plots the following
ordered pairs on a grid:
4
3
A(1,4)
2
B(0,0)
C(-3, -2)
D(-2, 4)
1
-4
-3
-2
-1
1
-1
-2
E(0, 3)
-3
F(-2, 0)
-4
2
3
4
Key Ideas:
• An ordered pair (x , y) is used to locate any point on
a Cartesian plane.
• All points located within the same quadrant have
the same signs for their x-coordinate and ycoordinate.
• Points on the x-axis have the value (x , 0).
• Points on the y-axis have the value (0 , y).
Homework:
MathLinks Pages 9 – 11
#5, 7, 9, 11, 14, 16