1. Geometry Agenda 1. ENTRANCE 2. Go over Practice 3. 3-5 Continued
5. EXIT

2. Practice

3. Chapter 3
3-5 Continued

4. Slope
The steepness of a line

5. Types of Slope
Positive
Negative
Zero No

6. Equations of Lines
A line is a set of points. Every line has an equation that relates the coordinates of these points.
ex: 2x - 3y = 14
(1, -4) (4, -2) (2.5, -3)
(-2, -6) (-0.5, -5) (7, 0)

7. Forms of a Line These are each different forms of the same equation.
2x - 3y = 14 Standard form
y = Slope-Intercept form
y + 4 = (x -1) Point-Slope form

8. Standard Form
This equation is of the form Ax + By = C. The x and y terms are on the left side and the constant is on the right side of the equation.
2x - 3y = 14

9. Slope-Intercept Form
This equation is of the form y = mx + b. The y term is on the left and the x term is on the right side of the equation. The value of m is the slope of the equation. The value of b is the y-intercept.
y =

10. Point-Slope Form This equation is of the form y – y1 = m(x – x1).
The y term is on the left and the x term is on the right side of the equation. The value of m is the slope of the equation. The values x1 and y1
are the coordinates of a
point on the line.
y + 4 = (x – 1)
m = (1, -4)

11. Example #1
Graph.

12. Example #2
Graph.

13. Example #3
Graph.

14. Example #4
Find the equation of a line with slope -3 that contains the point (-1, 4).

15. Example #5
Find the equation of a line that contains the points (6, 3) and (-4, 5).

16. Example #6
Find the equation of a horizontal line through the point (-3, 1).

17. Example #7
Find the equation of a vertical line through the point (1, -2).

18. Example #8
A truck ramp is being redesigned for a local moving company. What is the equation of the line that represents the ramp?

19. Example #9
The equation P = $300m + $2000 represents the total payment (P) after m number of months for purchasing a car from the local dealership.
What is the slope of the line represented by this equation?
What does the slope represent in this situation?
What is the y-intercept of the line?
What does the y-intercept represent in this situation?

20. Practice
WB 3-5 # 4, 8, 13, 14, 21, 27, 28, 36, 45, 46
EXIT