5-7 Ax + by = c form

1. 5-7 Ax + by = c form Miss battaglia – algebra 1 CP Objective: graph equations using x- and y-intercepts; write equations in Ax+by=c form; model situations with equations in the form ax+by=c.

2. Warm up • The choir director offers to stop at a fast food restaurant with 60 students after a performance. A discussion reveals that 35 students like cheeseburgers, 37 like pizza, 36 students like tacos, 22 students like cheeseburgers or pizza, 18 students like pizza or tacos, 23 students like tacos or cheeseburgers, and 15 students like all three choices. How many students like only one of the three fast food choices?

3. Graphing equations • Ax + By = C Form of a Linear Equation • Ax + By = C is a linear equation, where A and B cannot both be zero. • 3x + 4y = 8 • To make a quick graph, you can use the x- and y-intercepts. The • x-interceptis the x-coordinate of the point where a line crosses the x-axis.

4. graph • 3x + 4y = 8 • Find the x- and y-intercept

5. Find the x- and y-intercepts of each equation • a. 3x + 4y = 12 b. 2x – y = 4

6. Graph on a graphing calculator • 5x – 3y = 120 • Step 1: Write the equation in slope-intercept form. • Step 2: Find the x- and y-intercepts. • Step 3: Set the ranges to include the x- and y-axes and the intercepts. Then graph!

7. fitness • When you jog, you burn 7.3 calories/min. When you run, you burn 11.3 calories/min. Write an equation to find the times you would need to run and job in order to burn 500 calories.

8. example • Write an equation of the line with the slope - through the point (-1,7)

9. example • Write an equation of the line with the slope - through the point (4,2)

10. homework • Pg248-249 # 1, 4 – 7, 12a, 13, 14a, 20 – 22