1. Lesson 2-4 The Coordinate Plane
Applied Geometry
Lesson 2-4
The Coordinate Plane
Objective:
Learn to graph ordered pairs on a coordinate plane

2. Coordinate Plane Origin (0,0)
The number plane formed by two perpendicular number lines that intersect at their zero points to form a grid.
Origin (0,0)

3. Quadrants
The four regions of the coordinate plane II I
III IV

4. Ordered pair Ordered pair (x, y)
Coordinates: an ordered pair of real numbers used to locate a point on a coordinate plane.
(3, 5)
3 is the x-coordinate
5 is the y-coordinate

5. Graph Graph: the point in the coordinate plane.
Graphing: locating the point in the coordinate plane

6. Postulate 2-4 Completeness Property for Points in the Plane
Each point in a coordinate plane corresponds to exactly one ordered pair of real numbers. And vice versa.

7. Example B (-2, 4) C (0, -3) D (-3, -2)
Name the coordinates of B, C, and D.
B (-2, 4)
C (0, -3)
D (-3, -2)

8. Example Go right 2, down –3. A would be in IV quadrant.
Graph point A at (2, -3)
Describe its location
Go right 2, down –3.
A would be in IV quadrant.

9. Theorem
If a and b are real numbers, a vertical line contains all points (x,y) such that x = a, and a horizontal line contains all points (x, y) such that y = b.

10. Graph
y = 4
x = -3
x = 2
y = -1
x = 0

11. Homework
Pg – 14 all, 16 – 44 E