1. Chapter 4
4.6 Slope Intercept Form

2. Objectives Write a linear equation in slope-intercept form.
Graph a line using slope-intercept form.

3. Slope intercept form
You have seen that you can graph a line if you know two points on the line. Another way is to use the slope of the line and the point that contains the y-intercept.
This is y= mx+b also known as the slope intercept form

4. Example#1 Graph the line given the slope and y-intercept.

5. Example #2 Graph the line given the slope and y-intercept.
slope = 2, y-intercept = –3

6. Student guided practice
Do problems 1-4 in your book pg.272

7. Sloe-intercept form
you know the slope of a line and the y-intercept, you can write an equation that describes the line.

8. Example #3
If a line has a slope of 2 and the y-intercept is 3.Write the slope intercept form of the line.

9. Example#4
Write the equation that describes the line in slope-intercept form.
slope =1/4 ; y-intercept = 4

10. Example
Write the equation that describes the line in slope-intercept form.
slope = –9; y-intercept = 5/4

11. Student guided practice
Do problems 6 and 7 in your book page 272

12. Example
Write the equation that describes the line in slope-intercept form.

13. Example
Write the equation that describes the line in slope-intercept form.
slope = 2; (3, 4) is on the line.

14. Example
Write the equation in slope-intercept form. Then graph the line described by the equation.
A)y = 3x – 1
B) 2y + 3x = 6

15. Example
Write the equation in slope-intercept form. Then graph the line described by the equation.
Y=-4

16. Student guided practice
Do problems 10 to 12 in your book page 272

17. Application
A closet organizer charges a $100 initial consultation fee plus $30 per hour. The cost as a function of the number of hours worked is graphed below.

18. Application
a. Write an equation that represents the cost as a function of the number of hours.
Solution
Cost is
$30
for each hour
plus
$100 y = 30 •x +
100
An equation is y = 30x

19. Application
A caterer charges a $200 fee plus $18 per person served. The cost as a function of the number of guests is shown in the graph.
. Write an equation that represents the cost as a function of the number of guests.

20. Homework
Do problems in your book page 272

21. Closure Today we learned about the slope intercept form
Next class we are going to learned about point-slope form.