2. DEFINING SLOPE SECTION 5.2

3. Slope = = ________ is the ratio of vertical ______ to horizontal _____. Sloperise run rise SLOPEMAN My one weakness is that I can only run to the right.

4. Rise Run If I run uphill, then the slope of the line is positive. Lines with a positive slope go uphill from left to right. Remember, I can only run to the right!

5. Slopeman is going UPHILL so the slope is POSITIVE. Lines with POSITIVE slope go UP from left to right

6. Rise Run If I run DOWNHILL, then the slope of the line is NEGATIVE. Lines with a NEGATIVE slope go DOWN from left to right. Remember, I can only run to the right!

7. Slopeman is going downhill so the slope is negative.

8. EXAMPLE 1: Find the slope of the following lines. Rise Run 2 2 Slope=m = 1 We use the letter m to represent slope.

9. EXAMPLE 1: Find the slope of the following lines. 3 1 3 1 Slope is negative. m = -3

10. EXAMPLE 1: Find the slope of the following lines. 1 2 1 2 Slope is positive.

11. Plot the following points on the graph and find the slope. 1515 x y 4646 4 2 Slope is positive. +4 +2 +4 +2 2

12. 6464 x y 9191 -2 -8 Example 2: Find the slope between the following points without graphing. -2 -8

13. 3 -3 x y 5 -6 +6 Example 2: Find the slope between the following points without graphing. -6 +6

14. 29 -52 x y -31 14 -81 +45 Example 2: Find the slope between the following points without graphing. -81 +45

15. Sometimes when you must find the slope of a line without having a picture of the graph, it is easier to find the slope of a line using the following formula. Slope = when the two points are Example 3: Find the slope of the line containing the following points

16. Example 3: Find the slope of the line containing the following points

17. Choose any two points on the line and find the slope of the line. xy 4 3 1 3 +0 -3 +0 -3

18. The slope of any horizontal line is zero. If I tried to ski on this line, how fast would I travel? zero miles per hour

19. Choose any two points on the line and find the slope of the line. xy -2 1 -2 -3 -4 +0 -4 +0

20. What would happen if I tried to ski off this vertical cliff?

21. HELP !! I would have UNDEFINED body parts!! The slope of any vertical line is undefined.