1. Evaluate each expression when x = −2. 1.4x + 10 2.−3 + 11x 3. 4.8(x + 5) Warm-Up 10.1.15 2 −25 −1 24

2. Good to Know! The Commutative Property of Addition states that numbers can be added in any order. This can be applied in a linear equation. In Lesson 2.5, linear equations were shown in the form: y = b ± mx Based on the Commutative Property, this equation can also be written as: y = mx ± b For example, y = 7 + 2x  y = 2x + 7 y = 4 – 3x  y = –3x + 4 Notice that the “ – ” belongs to the rate of change and must move with it.

3. Use the linear equations given in the box to complete this activity. Step 1List the equation(s) that have a negative rate of change. Step 2List the equations(s) that have a positive y-intercept. Step 3Which equation has a start value of zero? How do you know?

4. Step 4Which equation has a rate of change equal to zero? How do you know? Step 5Create your own linear equation that fits the given description. a.A positive start value and negative rate of change. b.A rate of change equal to zero. c.A start value equal to zero. d.A negative rate of change and a negative y-intercept.

5. Use the linear equation to complete the input-output table: y = 3x + 8 Substitute each x-value into the equation to determine the y-values. Example 1

6. Good to Know! Any input-output table can be turned into ordered pairs and graphed. When dealing with linear equations, graphing is a great way to double-check the calculations as all points should be in a straight line. The graph below shows the ordered pairs from the table used in Example 3.

7. Complete the following table for the linear equation y = −2x + 1. xy −3 0 2 9 Exit Problem −17 −3 1 7