1. Drill #19* Find the x- and y– intercepts of the following equations in standard form, then graph each equation: 1.2x – 2y = 6 2.-3x + 4y = 12 3.2x + 3y = 8

2. Quiz Tomorrow Find the slope of a line Y- intercept X-intercept Graphing Linear Equations Parallel and Perpendicular Lines

3. Solve for y: In the standard form equation Ax + By = C What equation do you get? What form is it in? y = (-A/B)x + C/B

4. How To Graph (Standard Form) Standard Form = Ax + By = C The easiest way to graph an equation in standard form is to find the x- and y- intercepts X- intercept:Y- intercept:

5. Formulas from Standard Form If an equation is in standard form Ax + By = C Then X- intercept = C/A Y- Intercept = C/B Slope = -A/B

6. Graphing Linear Equations When an equation is in standard form: Find the x- and y- intercepts When an equation is in slope-intercept form: Use the slope and the y- intercept

7. How To Graph (Slope Intercept) To graph an equation in slope intercept form use the slope (m) and the y- intercept (b) 1.Plot b (the y- intercept) 2.Use the slope to find a second point 3.Connect the points and draw a line

8. Example: Graph the following equation that is in slope intercept form: y = 2x – 2 What is the slope? What is the y- intercept?

9. Graph the following equations (#18*) 4.y = -2x + 3 5.y = ½ x – 2

10. Find the equation of the following: 6. Hint: Use the slope and y- intercept. x y -4 2

11. Slope (20.)** Slope: The ration of the change in vertical units to the change in horizontal units (RISE OVER RUN). The formula for the slope m of the line passing throughand is given by. That is the change in the y coordinate (RISE) over the change in the x coordinate (RUN)

12. Find the slope Find the slope of the line passing through the following points: 7.7x + 5y = 6 8.y = - ½ x - 5 9.y = 6

13. Parallel Lines (21. & 22.) ** Parallel Lines: In a plane, non-vertical lines with the same slope are parallel. Perpendicular Lines: In a plane, two oblique lines are perpendicular if and only if the product of their slopes is -1.

14. Determine if the following lines are parallel, perpendicular, or neither: 10. y = ½ x + 3 y = -2x – 1 11. y = 4x + 1 y = ¼ x – 2 12. y = 3 y = -1