1. Writing Linear Equations
Slope – Intercept form

2. Review: Slope Formula

3. Review: X and Y- intercepts
The x-intercept of a graph is the point where the graph crosses the x-axis.
The y-intercept of a graph is the point where the graph crosses the y-axis.
Example: x-intercept = (3, 0) y-intercept = (0, 1)

4. b represents the y-intercept
Slope – Intercept Form
y = mx + b
m represents the slope
b represents the y-intercept

5. To find the slope and y-intercept of an equation, write the equation in slope-intercept form: y = mx + b.
Find the slope and y-intercept.
y = 3x – 7
y = mx + b

6. Find the slope and y-intercept.
2) y = x
y = mx + b
y = x + 0
3) y = 5
y = 0x + 5

7. Find the slope and y-intercept. 4) 5x - 3y = 6

8. Find the slope and y-intercept. 5) 2y + 2 = 4x

9. Find the slope and y-intercept of y = -2x + 4

10. Writing Equations
When asked to write an equation, you need to know two things – slope (m) and y-intercept (b).
There are three types of problems you will face.
Step 1 – find m
Step 2 – find b
Step 3 – write the equation

11. Writing Equations – Type #1
Write an equation in slope-intercept form of the line that has a slope of 2 and a y-intercept of 6.

12. EXAMPLE
Write an equation in slope-intercept form of the line that has a slope of -3 and a y-intercept of -4.

13. Write the equation of a line that has a y-intercept of -3 and a slope of -4.

14. Writing Equations – Type #2
Write an equation of the line that has a slope of 3 and goes through the point (2,1).

15. EXAMPLE
Write an equation of the line that has a slope of -2 and goes through the point (3,-4).

16. Writing Equations – Type #3
Write an equation of the line that goes through the points (-2, 1) and (4, 2).

17. Writing Equations – Type #3

18. EXAMPLE
Write an equation of the line that goes through the points (-2, 5) and (4, 8).

19. Write an equation of the line that goes through the points (0, 1) and (1, 4).