1. Coordinate Geometry Monroe HS Math Department Monroe HS Math Department

2. Definition Grid – A pattern of horizontal and vertical lines, usually forming squares.

3. Definition Coordinate grid – a grid used to locate a point by its distances from 2 intersecting straight lines. A B C D E 12345 What are the coordinates for the house?

4. Definition x axis – a horizontal number line on a coordinate grid. 1234506 x

5. Hint x is the shortest and likes to lie down horizontally. 1234506 x

6. Definition y axis – a vertical number line on a coordinate grid. 1 2 3 4 5 0 6 y

7. Hint y is the tallest and stands upright or vertically. 1 2 3 4 5 0 6 y

8. Definition Coordinates – an ordered pair of numbers that give the location of a point on a grid. (3, 4) 1 2 3 4 5 0 6 1234506 (3,4)

9. Hint The first number is always the x or first letter in the alphabet. The second number is always the y the second letter in the alphabet. 1 3 2 4 5 0 6 1234506 (3,4)

10. How to Plot Ordered Pairs Step 1 – Always find the x value first, moving horizontally either right (positive) or left (negative). 1 3 2 4 5 0 6 1234506 (2, 3) y x

11. How to Plot Ordered Pairs Step 2 – Starting from your new position find the y value by moving vertically either up (positive) or down (negative). 1 3 2 4 5 0 6 1234506 (2, 3) y x

12. How to Find Ordered Pairs Step 1 – Find how far over horizontally the point is by counting to the right (positive) or the left (negative). 1 3 2 4 5 0 6 1234506 (5, ) y x

13. How to Find Ordered Pairs Step 2 – Now count how far vertically the point is by counting up (positive) or down (negative). 1 3 2 4 5 0 6 1234506 (5,4) y x

14. What is the ordered pair? 1 3 2 4 5 0 6 1234506 (3,5) y x

15. What is the ordered pair? 1 3 2 4 5 0 6 1234506 (2,6) y x

16. What is the ordered pair? 1 3 2 4 5 0 6 1234506 (4,0) y x

17. What is the ordered pair? 1 3 2 4 5 0 6 1234506 (0,5) y x

18. What is the ordered pair? 1 3 2 4 5 0 6 1234506 (1,1) y x

19. Four Quadrants of Coordinate Grid When When the number lines are extended into the negative number lines you add 3 more quadrants to the coordinate grid. -2 0 1 2 -3 3 -2012-33 y x

20. Four Quadrants of Coordinate Grid If the x is negative you move to the left of the 0. -2 0 1 2 -3 3 -2012-33 x = -2 y x

21. Four Quadrants of Coordinate Grid If the y is negative you move down below the zero. -2 0 1 2 -3 3 -2012-33 y = -3 y x

22. How to Plot in 4 Quadrants Step 1 - Plot the x number first moving to the left when the number is negative. -2 0 1 2 -3 3 -2012-33 (-3, -2) y x

23. How to Plot in 4 Quadrants Step 2 - Plot the y number moving from your new position down 2 when the number is negative. -2 0 1 2 -3 3 -2012-33 (-3, -2) y x

24. How to Plot in 4 Quadrants When x is positive and y is negative, plot the ordered pair in this manner. -2 0 1 2 -3 3 -2012-33 (2, -2) y x

25. How to Plot in 4 Quadrants When x is negative and y is positive, plot the ordered pair in this manner. -2 0 1 2 -3 3 -2012-33 (-2, 2) y x

26. Plot This Ordered Pair -2 0 1 2 -3 3 -2012-33 (-3, -3) y x

27. Plot This Ordered Pair -2 0 1 2 -3 3 -2012-33 (-1, 2) y x

28. Plot This Ordered Pair -2 0 1 2 -3 3 -2012-33 (1, -1) y x

29. Plot This Ordered Pair -2 0 1 2 -3 3 -2012-33 (2, -2) y x

30. Plot This Ordered Pair -2 0 1 2 -3 3 -2012-33 (-3, -2) y x