Section 7.2Graphing Linear Equations

1. Rearrange the equation into y = mx + b form. (Solve for y)

2. Make an x|y table. Choose any 3 values for x.

3. Sub each x value into the equation and solve for y.

4. Plot each (x, y) point and connect with a straight line.

Method 1: Plotting points

1. y = 3x – 2

2. 4x + 3y = -9

EX: Make a table and graph

1. Set y = 0 and solve for x. This point is the x-intercept (a, 0)

2. Set x = 0 and solve for y. This point is the y-intercepts, (0, b)

3. Select one other x-value and plug into find y. This gives 3rd point, (x, y)

4. Plot all three points and connect with a straight line.

Method 2: Using Intercepts

1. 2x – y = 4

2. 5x + 2y = -10

EX: Graph using intercepts

The graph of the equation x = a is a vertical line at a on the x-axis.

The graph of the equation y = b is a horizontal line at b on the y-axis.

Vertical and Horizontal Lines

1. x = ½

2. y = -3

EX: Graph

1. Review section 7.1 and 7.2 material (a little this week, and some next week), so you don’t forget it all! There are lots of practice problems in the text, and you have a review packet.

2. If you have to retake ch 3, study that material. Ch 3 retakes will be given during class on Mon, Jan 3rd. If you don’t have to retake, you don’t need to come on that day.

Over break…