3. SUMMARY
POSITIVE SLOPE
NEGATIVE SLOPE
ZERO SLOPE
UNDEFINED SLOPE

4. Examples Determine the slope of the given line. a. b. c.

5. The Special Cases Determine the slope of the given line. a. b.

6. Examples 7. Determine whether the slope of each line is positive, negative, zero, or undefined. a. b. c. d.

7. Slope Formula
The slope of a line is the ratio of _______________ __________________________________________ to ________________________________________ between any two different points on the line. ** Slope is ALWAYS __________________________

8. slope = the difference in y-values (dependent)
the distance in x-values(independent)

9. Find the slope of the line that contains the points (2, 5) and (8, 1).

10. Try It!
Find the slope of the line that contains the points (5, -7) and (6, -4).
Find the slope of the line that contains the points (¾, ⁷⁄₅) and (¼ ,⅖).

11. Identify the independent and dependent variables
You run 7 miles in one hour and 21 miles in three hours. Find the slope.
You can bake 12 dozen cookies in 2.5 hours and 25 dozen in 5 hours. Find the slope.

12. Sometimes you are not given two points to use in the formula
Sometimes you are not given two points to use in the formula. You might have to choose two points from a graph or a table.

13. Try it!

14. Slope – Intercept Form of Linear Equations
One way to graph the equation of a line is to use _____________ ______________________. Examples 1. Graph of the line that goes through the points (-2, 3) and (4, 5). What is the slope of the line?

15. You can also graph the equation of a line using the __________________ and __________________________ of the line!

16. Examples Graph the line of the equation with the given slope and y-intercept. 2. slope = y-intercept = 4
STEP 1
STEP 2
STEP 3

17. Examples Graph the line of the equation with the given slope and y-intercept. 3. slope = 2 y-intercept = -3

18. Try It! Graph the line of the equation with the given slope and y-intercept. 4. slope = 5. slope = y-intercept = 1 y-intercept = 0

19. SLOPE – INTERCEPT FORM of LINEAR EQUATION
Any linear equation can be written in slope-intercept form by ___________________________________________________.

20. Examples Write the equation that describes the line in slope – intercept form. 6. slope = 7. slope = -9 y-intercept = 4 y-intercept =

21. Try It! Write the equation that describes the line in slope – intercept form. 8. slope = 9. slope = 0 y-intercept = -2 y-intercept = 15

22. Examples Write the equation that describes the line in slope-intercept form. 10.

23. Examples Write the equation in slope – intercept form
Examples Write the equation in slope – intercept form. Then graph the line described by the equation y + 3x = 6

24. Examples Write the equation in slope – intercept form
Examples Write the equation in slope – intercept form. Then graph the line described by the equation x + 2y = -10

25. Examples Write the equation in slope – intercept form
Examples Write the equation in slope – intercept form. Then graph the line described by the equation. 15. y = -3