1. Determining an Equation of a Line
Chapter 8
Section 8.5

2. Objective
Students will find an equation of a line given the slope and one point on the line, or given two points on the line

3. Concept
You have learned to graph a line when given its equation. Now you will learn to find an equation of a line when given information about its graph.

4. Equation of a line y = mx + b m = slope b = y-intercept
Concept
Equation of a line y = mx + b m = slope b = y-intercept

5. Concept
Answers will be in slope-intercept form (y = mx + b) Given slope and one point – fill in y, x, and m into the equation and solve for b, write equation Given two points – find m, choose 1 order pair and fill in y, x, and m into the equation and solve for b, write equation

6. Write an equation of a line that has slope 2 and y-intercept 3
Example
Write an equation of a line that has slope 2 and y-intercept 3

7. Example
Write an equation of a line that has slope -4 and x-intercept 3

8. Example
Write an equation of a line that has slope 2 and passes through (1, 10)

9. Example
Write an equation of a line that has slope -2 and passes through (-4, 5)

10. Example
Write an equation of the line that passes through the points (-2, 5) and (4, 8)

11. Example
Write an equation of the line that passes through the points (1, 1) and (2, 4)

12. Questions

13. Assignment
Worksheet