1. Algebra 1 Solve 13 = + 5. y3y3 24 = y Simplify. 13 – 5 = + 5 – 5Subtract 5 from each side. y3y3 8 = Simplify. y3y3 3 8 = 3 Multiply each side by 3. y3y3 Check: 13 = + 5 y3y3 13 + 5 Substitute 24 for y. 24 3 13 8 + 5 13 = 13 Solving Two-Step Equations Additional Examples Lesson 3-1

2. Algebra 1 A music store sells a used guitar for $120. This is $25 more than the cost of a new guitar of the same brand. What is the cost of a new guitar? 1212 120 = 25 + c 1212 120 – 25 = 25 – 25 + cSubtract 25 from each side. 1212 95 = c Simplify. 1212 Relate:cost of used guitar is $25 more than the cost of the new guitar 1212 2 95 = 2 c Multiply each side by 2. 1212 190 = c Simplify. The new guitar costs $190. Define:Let = the cost of the new guitar. c Write: $120 = $25 + c 1212 Solving Two-Step Equations Lesson 3-1 Additional Examples

3. Algebra 1 You order iris bulbs from a catalog. Iris bulbs cost $.90 each. The shipping charge is $2.50. If you have $18.50 to spend, how many iris bulbs can you order? Relate: cost per iris times number of iris bulbs plus shipping equals amount to spend. 0.90b + 2.50 = 18.50 0.90b + 2.50 – 2.50 = 18.50 – 2.50Subtract 2.50 from each side. 0.90b = 16Simplify. Define: Let b = the number of bulbs you order. Write: 0.90 b + 2.50 = 18.50 Solving Two-Step Equations Additional Examples Lesson 3-1

4. Algebra 1 You can order 17 bulbs. b = 17.7 0.90b 0.90 = 16 0.90 Divide each side by 0.90. Simplify. (continued) Check: Is the solution reasonable? You can only order whole iris bulbs. Since 18 bulbs would cost 18 0.90 = 16.20 plus $2.50 for shipping, which is more than $18.50, you can only order 17 bulbs. Solving Two-Step Equations Additional Examples Lesson 3-1

5. Algebra 1 Solve 8 = + 4. Justify each step. 96=cSimplify. c 24 8 – 4= + 4 – 4Subtraction Property of Equality c 24 4=Simplify. c 24 24(4)=(24) ( ) Multiplication Property of Equality c 24 Solving Two-Step Equations Additional Examples Lesson 3-1