This document provides a lesson on slope-intercept form of a line. Slope-intercept form is represented by the equation y = mx + b, where m is the slope and b is the y-intercept. Given the slope and y-intercept, you can write the equation of the line and graph it. You can also determine if a given point lies on the line by plugging it into the equation - if the left and right sides are equal, the point is on the line. The lesson explains how to identify the slope and y-intercept from an equation, write the equation given slope and y-intercept values, and check if points are on lines.

1. Slope Intercept Form Lesson 5.4a

2. Slope intercept form An equation that shows the slope and the y-intercept.

3. y = mx + b (x,y) => any point on the line m => slope b => y-intercept When you know both, you can graph the line!

4. Identify the slope and y-intercept: y = 2x + 1 m = y int =

5. Identify the slope and y-intercept: y = 3x m = y int =

6. Identify the slope and y-intercept: y – ¼ = x m = y int =

7. Point on the line You may be given a point to see if it’s on the line.

8. Point on the line Plug the point into the equation. If the sides = each other then the point is on the line.

9. Point on the line If the sides ≠ each other, then the point is not on the line.

10. Is the point on the line? y = ½ x – 4 (2,-3) -3 = ½ (2) - 4 -3 = 1 – 4 -3 = -3 YES

11. Is the point on the line? y = 1/5 x – 4 (-3,2) 2 = 1/5 (-3) – 4 2 = -3/5 – 4 2 = -23/5 NO

12. Write an equation You may be given the slope and the y-int and asked to write an equation.

13. Write an equation m = 3 & b = 2 y = 3x + 2 m = -2 & b = 0 y = -2x

14. Write an equation m = ½ & b = 4 y = ½ x + 4

15. Review What is slope intercept form? For what does the m stand? the b?

16. Review How do you determine if a point is on a line?