2. MAT 150 Module 2 – Linear Functions Lesson 2 – Graphing Linear Functions

3. Graphing linear equations There are three methods we can use to graph lines. Make a table of values and plot points Use the x- and y- intercepts Use the slope and y- intercept

4. Graphing linear equations The first method is to graph the line by plotting points. find at least two points on the line Plot the points on the coordinate plane and draw the line through them. plug in any numbers for x into the equation

5. Example 1 – Plotting points Graph the equation y = -2x + 5 by plotting points.

6. Example 1 – Solution Graph the equation y = -2x + 5 by plotting points.

7. Graphing linear equations The second method is to find and plot the x and y intercepts. The intercepts are the points where the line crosses the x or y axis. www.coolmath.com

8. Graphing linear equations We can find the x- intercept by plugging in y = 0. We can find the y- intercept by plugging in x = 0. When you have found the two intercepts, plot them and draw the line through them. http://2012books.lardbucket.org/books/begin ning-algebra/s06-03-graph-using- intercepts.html

9. Example 2 - Intercepts

10. Graphing linear equations The third method is to use the slope- intercept form of the equation, which is. m is the slope b is the y-intercept y = mx + b

11. Example 3 – Slope and y-intercept

12. Knowledge Check Graph the equation 3x  4y = 12 using any of the three methods. Use the best method for the given problem.