1. Hands-on Activity: Competition Time
Matching: Slope-Intercept Form & Graph

2. Home-Learning Assignment #3 - Review

3. Where m is the slope and b is the intercept
Name:
Date:
Period:
Topic: 1. Point-Slope Form Standard Form
Essential Question: What can be used to write and graph the equation of a line? Which form would better help me graph & write linear equations?
Quick Review:
What we Know so far….
Slope Intercept Form
Where m is the slope and b is the intercept

4. By the end of today’s class you will be able to write and graph
Previously you learned one strategy for writing a linear equation when given the slope and a point on the line..
In this lesson you will learn a different strategy – one that uses the point-slope form of an equation of a line
By the end of today’s class you will be able to write and graph
linear equations using point-slope form
Objective:

5. The New Stuff… Point- Slope Form
Point- Slope form is:
Where m is the slope and (x1,y1) is the given point

6. Example #1
Write the equation of the line that goes through the point (2, –3) and has a slope of 4.
Point = (2, –3)
Slope = 4
Starting with the point – slope form
y – y1 = m (x – x1)
Plug in the y-value, the slope, and the x-value to get
y + 3 = 4 (x – 2)
Notice, that when you replaced the “y1” it became “+3”.

7. Write the Equation in Point-Slope Form
Step 1: Plug it in

8. What is the graph of y – 1 = (x – 2)?4 3 5 -1 -2 -3 -4 -5

9. Using two points to write an equation in point-slope form
???
Using two points to write an equation in point-slope form
Can you write the equation of a line in point-slope form that passes through (-3,6) and (1,-2)

10. Using two points to write an equation in point-slope form
???
Using two points to write an equation in point-slope form 1 2 4 3 5 -1 -2 -3 -4 -5
(2,2)
(0,-3)

11. Standard Form
Ax + By = C

12. The word “intercept” means to cross.
Vocabulary
The word “intercept” means to cross.
x-intercept
- the point (ordered pair) where a line crosses the x-axis.
y-intercept
- the point (ordered pair) where a line crosses the y-axis.

13. To find an intercept, set the other variable equal to zero.
Using Standard Form:
To find an intercept, set the other variable equal to zero.
Ax + By = C
3x – 5y = 15

14. (Find x & y-intercept):
Your Turn
(Find x & y-intercept):
1) x + 4y = 24
2) 7x + 8y = 21

15. Graph using X & Y-intercepts:

16. Graphing Horizontal Lines:
Slope is zero.
Equation form is y = #.
a) y = -2
b) y = 3
c) y = 1

17. Graphing Vertical Lines:
Slope is undefined.
Equation form is x = #.
a) x = -1
b) x = 3
c) x = 4

18. Transforming to Standard Form (Ax + By = C):
y = 3x + 4
y = 3/7x + 4
y – 2 = - 1/3(x + 6)

19. How can I write the following standard form in slope-intercept form?
Making the connection:
How can I write the following point-slope form in slope-intercept form?
y + 3 = 4 (x – 2)
How can I write the following standard form in slope-intercept form?
-4x + y = - 11

20. Practice:
Page
(2-6, 12, 35)
Page 323 (6)

21. Review for Exam #4

22. Vocabulary & Forms Review HLA #4: Point-Slope Form & Standard Form
Wrap-Up:
Vocabulary & Forms Review
HLA #4: Point-Slope Form & Standard Form
Page 316 – 318 (14, 16, 39)
Page 324 (12, 14)