2. SLOPE

3. OBJECTIVES  TO UNDERSTAND WHAT POSITIVE AND NEGATIVE SLOPE LOOK LIKE  TO UNDERSTAND WHAT ZERO AND UNDEFINED SLOPE LOOK LIKE  TO UNDERSTAND WHAT SLOPES OF 1 AND -1 LOOK LIKE  TO UNDERSTAND WHAT SLOPES GREATER AND LESS THAN 1 LOOK LIKE

4. SLOPE Sometimes, on mountain roads, you’ll see signs warning cars and trucks about very steep hills. Often the sign uses a percent to show how steep (0% would be flat and 100% would be a cliff), and a picture to show whether it’s steep going up or down. 12% 5%

5. You can use the same idea to measure the steepness of a line. A line (like line a) that moves upward from left to right has a positive slope. A line (like line b) that moves downward from left to right has a negative slope. a b Positive slope Negative slope POSITIVE AND NEGATIVE SLOPE

6. ZERO SLOPE AND UNDEFINED SLOPE If a line is flat from left to right or what we call horizontal, it has a slope of 0. If a line is straight up or down or what we call vertical, it has no slope, also known as an undefined slope. Zero slope Undefined slope

7. Y X A line with a slope of 1 will go up to the right and make angles of 45° with both axes on a square coordinate system. A line with a slope of -1 will go up to the left and will also make angles of 45° with both axes on a square coordinate system. Slope of 1 Slope of -1 SLOPES OF 1 AND -1

8. Y X Lines with a slope greater than 1 are steeper than lines with a slope of 1. Lines with a slope between 0 and 1 are less steep than lines with a slope of 1. It can be helpful to think of lines with a slope of 1 as the “middle case” between steeper and less steep. Slope greater than 1. Slope between 0 and 1. SLOPES GREATER AND LESS THAN 1

9. Question time! You will be given three lines to look at, and then answer the questions using the knowledge you have learned. Y X a b c Which line has a NEGATIVE slope? a b c

10. You can use the same idea to measure the steepness of a line. A line (like line a) that moves upward from left to right has a positive slope. A line (like line b) that moves downward from left to right has a negative slope. a b Positive slope Negative slope REMEMBER: POSITIVE AND NEGATIVE SLOPE TRY AGAIN

11. REMEMBER: ZERO SLOPE AND UNDEFINED SLOPE If a line is flat from left to right or what we call horizontal, it has a slope of 0. If a line is straight up or down or what we call vertical, it has no slope, also known as an undefined slope. Zero slope Undefined slope TRY AGAIN

12. Y X a b c a b c Which line has a slope of 1? YOU ARE A SUPER SLOPE SLUETH! WELL DONE!

13. REMEMBER: ZERO SLOPE AND UNDEFINED SLOPE If a line is flat from left to right or what we call horizontal, it has a slope of 0. If a line is straight up or down or what we call vertical, it has no slope, also known as an undefined slope. Zero slope Undefined slope TRY AGAIN

14. Y X A line with a slope of 1 will go up to the right and make angles of 45° with both axes on a square coordinate system. A line with a slope of -1 will go up to the left and will also make angles of 45° with both axes on a square coordinate system. Slope of 1 Slope of -1 REMEMBER: SLOPES OF 1 AND -1 TRY AGAIN

15. Y X a b c a b c Which line has an UNDEFINED slope? SWEET SLOPE CHOICE!

16. You can use the same idea to measure the steepness of a line. A line (like line a) that moves upward from left to right has a positive slope. A line (like line b) that moves downward from left to right has a negative slope. a b Positive slope Negative slope REMEMBER: POSITIVE AND NEGATIVE SLOPE TRY AGAIN

17. REMEMBER: ZERO SLOPE AND UNDEFINED SLOPE If a line is flat from left to right or what we call horizontal, it has a slope of 0. If a line is straight up or down or what we call vertical, it has no slope, also known as an undefined slope. Zero slope Undefined slope TRY AGAIN

18. Y X a b c a b c Which line has a slope LESS than 1? SLOPETACULAR!

19. REMEMBER: ZERO SLOPE AND UNDEFINED SLOPE If a line is flat from left to right or what we call horizontal, it has a slope of 0. If a line is straight up or down or what we call vertical, it has no slope, also known as an undefined slope. Zero slope Undefined slope TRY AGAIN

20. Y X Lines with a slope greater than 1 are steeper than lines with a slope of 1. Lines with a slope between 0 and 1 are less steep than lines with a slope of 1. It can be helpful to think of lines with a slope of 1 as the “middle case” between steeper and less steep. Slope greater than 1. Slope between 0 and 1. REMEMBER: SLOPES GREATER AND LESS THAN 1 TRY AGAIN

21. Y X a b c a b c Which line has a POSITIVE slope? YOU ARE A SLICK SLOPESTER DUDE!

22. REMEMBER: ZERO SLOPE AND UNDEFINED SLOPE If a line is flat from left to right or what we call horizontal, it has a slope of 0. If a line is straight up or down or what we call vertical, it has no slope, also known as an undefined slope. Zero slope Undefined slope TRY AGAIN

23. You can use the same idea to measure the steepness of a line. A line (like line a) that moves upward from left to right has a positive slope. A line (like line b) that moves downward from left to right has a negative slope. a b Positive slope Negative slope REMEMBER: POSITIVE AND NEGATIVE SLOPE TRY AGAIN

24. Y X a b c a b c Which line has a slope of ZERO? SLOPESATIONAL!

25. You can use the same idea to measure the steepness of a line. A line (like line a) that moves upward from left to right has a positive slope. A line (like line b) that moves downward from left to right has a negative slope. a b Positive slope Negative slope REMEMBER: POSITIVE AND NEGATIVE SLOPE TRY AGAIN

26. REMEMBER: ZERO SLOPE AND UNDEFINED SLOPE If a line is flat from left to right or what we call horizontal, it has a slope of 0. If a line is straight up or down or what we call vertical, it has no slope, also known as an undefined slope. Zero slope Undefined slope TRY AGAIN

27. Y X a b c a b c Which line has a slope of -1? STUPENDOUS SLOPE ACTION!

28. REMEMBER: ZERO SLOPE AND UNDEFINED SLOPE If a line is flat from left to right or what we call horizontal, it has a slope of 0. If a line is straight up or down or what we call vertical, it has no slope, also known as an undefined slope. Zero slope Undefined slope TRY AGAIN

29. Y X A line with a slope of 1 will go up to the right and make angles of 45° with both axes on a square coordinate system. A line with a slope of -1 will go up to the left and will also make angles of 45° with both axes on a square coordinate system. Slope of 1 Slope of -1 REMEMBER: SLOPES OF 1 AND -1 TRY AGAIN

30. Y X a b c a b c Which line has a slope GREATER than 1? YOU ARE A SMASHING SLOPE STUD!

31. You can use the same idea to measure the steepness of a line. A line (like line a) that moves upward from left to right has a positive slope. A line (like line b) that moves downward from left to right has a negative slope. a b Positive slope Negative slope REMEMBER: POSITIVE AND NEGATIVE SLOPE TRY AGAIN

32. Y X Lines with a slope greater than 1 are steeper than lines with a slope of 1. Lines with a slope between 0 and 1 are less steep than lines with a slope of 1. It can be helpful to think of lines with a slope of 1 as the “middle case” between steeper and less steep. Slope greater than 1. Slope between 0 and 1. REMEMBER: SLOPES GREATER AND LESS THAN 1 TRY AGAIN

33. Click here to return to the beginning Click here to end the show. CONGRATULATIONS YOU HAVE COMPLETED THE SUPER SLICK SLOPE STUDY SYSTEM! You should now have a better understanding of positive and negative slope, zero slope and undefined slope, slopes of 1 and -1, and of slopes greater and less than 1.