1. 13.4 – Slope and Rate of Change
Slope is a rate of change.

2. 13.4 – Slope and Rate of Change

3. 13.4 – Slope and Rate of Change

4. 13.4 – Slope and Rate of Change
Slope of any Vertical Line

5. 13.4 – Slope and Rate of Change
Slope of any Horizontal Line

6. 13.4 – Slope and Rate of Change
Find the slope of the line defined by:

7. 13.4 – Slope and Rate of Change
Alternative Method to find the slope of a line
If a linear equation is solved for y, the coefficient of the x represents the slope of the line.

8. 13.4 – Slope and Rate of Change
If a linear equation is solved for y, the coefficient of the x represents the slope of the line.

9. 13.4 – Slope and Rate of Change
Parallel Lines are two or more lines with the same slope.
These two lines are parallel.

10. 13.4 – Slope and Rate of Change
Perpendicular Lines exist if the product of their slopes is –1.
These two lines are perpendicular.

11. 13.4 – Slope and Rate of Change
Are the following lines parallel, perpendicular or neither?
NEITHER

12. 13.4 – Slope and Rate of Change
Are the following lines parallel, perpendicular or neither?
These two lines are perpendicular.

13. 13.4 – Slope and Rate of Change
For every twenty horizontal feet a road rises 3 feet. What is the grade of the road?

14. 13.4 – Slope and Rate of Change
The pitch of a roof is a slope. It is calculated by using the vertical rise and the horizontal run. If a run rises 7 feet for every 10 feet of horizontal distance, what is the pitch of the roof?

16. 13.5 – Equations of Lines
Slope-Intercept Form– requires the y-intercept and the slope of the line.
m = slope of line
b = y-intercept

17. 13.5 – Equations of Lines Slope-Intercept Form: m = slope of line
b = y-intercept

18. 13.5 – Equations of Lines Slope-Intercept Form: m = slope of line
b = y-intercept

19. 13.5 – Equations of Lines Slope-Intercept Form: m = slope of line
b = y-intercept

20. 13.5 – Equations of Lines
Write an equation of a line given the slope and the y-intercept.

21. 13.5 – Equations of Lines
Point-Slope Form – requires the coordinates of a point on the line and the slope of the line.

22. 13.5 – Equations of Lines
Point-Slope Form – requires the coordinates of a point on the line and the slope of the line.

23. 13.5 – Equations of Lines
Point-Slope Form – requires the coordinates of a point on the line and the slope of the line.

24. 13.5 – Equations of Lines Writing an Equation Given Two Points
1. Calculate the slope of the line.
2. Select the form of the equation.
a. Standard form
b. Slope-intercept form
c. Point-slope form
3. Substitute and/or solve for the selected form.

25. 13.5 – Equations of Lines Writing an Equation Given Two Points
Given the two ordered pairs, write the equation of the line using all three forms.
Calculate the slope. or

26. 13.5 – Equations of Lines Writing an Equation Given Two Points
Point-slope form

27. 13.5 – Equations of Lines Writing an Equation Given Two Points
Slope-intercept form

28. 13.5 – Equations of Lines Writing an Equation Given Two Points
Standard form
LCD: 4

29. 13.5 – Equations of Lines Solving Problems
The pool Entertainment company learned that by pricing a pool toy at $10, local sales will reach 200 a week. Lowering the price to $9 will cause sales to rise to 250 a week.
a. Assume that the relationship between sales price and number of toys sold is linear. Write an equation that describes the relationship in slope-intercept form. Use ordered pairs of the form (sales price, number sold).
b. Predict the weekly sales of the toy if the price is $7.50.

30. 13.5 – Equations of Lines
Solving Problems

31. 13.5 – Equations of Lines Solving Problems
Predict the weekly sales of the toy if the price is $7.50.