1. Welcome to Unit 8: LINEAR Functions

2. Introduction to Slopes

3. Slopes in Real Life

4. What is the slope of a line?
Rate of change
Rise/Run
Steepness of a line
Change in Y/Change in X

5. Ways to solve for SLOPE
1) Graphs
2) Tables
3) Points
4) Equations

6. Finding slope using a graph
Rise is -1
Run is 2
−1 2

7. Example: Finding slope using a graph

8. Volunteer?

9. Find the slope of the line that passes through two given points.
Example: R(1,2), S(-4,3)
Hint: Use the slope formula.

10. Find the slope of the line that passes through two given points.
Given: A(4,6), B(3,8)
Hint: Use the slope formula.

11. Volunteer?
Given: C(6,-2), D(10,4)

12. Slope Formula: Using a table to find the slopeX Y 1 12 3 9 5 6 7
𝐶ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑌 𝐶ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑋 = Slope
9−12 3−1 = −3 2 =− 3 2

13. Slope Formula: Using a table to find the slopeX Y 2 1 4 6 3 8 10 5

14. Volunteer? X Y -3 -2 -9
-15
-21
-27

15. Try This One…
The slope of a line that goes through the points (r, 6) and (4, 2) is 4. Find r.

16. To solve this, plug the given information into the formula
The slope of a line that goes through the points (r, 6) and (4, 2) is 4. Find r.
To solve this, plug the given information into the formula

17. To solve for r, simplify and write as a proportion.
Cross multiply.
1(-4) =
4(4 – r)

18. Simplify and solve the equation. 1(-4) = 4(4 – r)
The ordered pairs are (5, 6) and (4, 2)

19. SLOPE DUDE

20. Slope
To determine if slope is positive or negative, look at the line from left to right (just like you read).
Down …negative. UP…positive.

21. Formula for Slope A way to remember which value goes on top.2 Y 1 -Y
m = 2 X 1
- X
Keep the pairs together.

22. y horizontal line = any number What does an upside-down h look like?
Is always a horizontal line.
Zero slope

23. x Vertical line = any number
What does an upside-down and right-side up V look like?
= any number
Is always a vertical line. x
Undefined slope