1. Introduction to the coordinate Plane

2. What is the coordinate plane?
Coordinate plane: The plane formed by two perpendicular lines called the x-axis and y- axis.
x-axis: the horizontal number line.
y-axis: the vertical number line.

3. What is the coordinate plane?

4. Ordered pairs
Ordered pair: a pair of numbers that represents a unique point in the coordinate plane. The first value is the x coordinate and the second value is the y coordinate.
Ex. 1: (2, 3) → 2 is the x coordinate and 3 is the y coordinate

5. The origin
Origin: the center of the coordinate plane. It has coordinates (0, 0). It is the point where we always start when we are graphing.

6. How do I plot a point?
To graph a point in the coordinate plane start at the origin. Look first at the x coordinate. If the x coordinate is positive, move that many spaces to the right. If the x coordinate is negative, move that many spaces to the left. From your x coordinate location look at the y coordinate. If the y coordinate is positive, go up that many spaces. If the y coordinate is negative, go down that many spaces.

7. Let’s try plotting

8. Let’s try plotting

9. Name the coordinates of a point

10. Name the coordinates of a point

11. Name the coordinates of a point

12. Name the coordinates of a point

13. What quadrant is a point in?
Quadrant I (x, y)
Positive x and positive y
Quadrant II (-x, y)
Negative x and positive y
Quadrant III (-x, -y)
Negative x and negative y
Quadrant IV (x, -y)
Positive x and negative y
Points on the x-axis or y-axis do not belong to any quadrant.

14. Let’s try a few D F E A C B

15. Let’s try a few D X-axis F E Quadrant IV Quadrant III A Quadrant I
Y-axis C
Quadrant II B

16. Name the coordinates of a point

17. Which quadrant?
(3, -2)
(-1, 4)
(-5, 0)
(-4, -4)
(0, -5)

18. Which quadrant? (3, -2) Quadrant IV (-1, 4) Quadrant II (-5, 0) x-axis
(-4, -4) Quadrant III
(0, -5) y-axis
Now list the coordinates for one point that is in Quadrant I.