p.341: 7 The Strauss family is deciding between two lawn-care service. Green Lawn charges a $49 startup fee, plus $29 per month. Grass Team charges a $25 startup fee, plus $37 per month. a. In how many months will both lawn-care services cost the same? What will that cost be? 3 months; $136 b. If the family will use the service for only 6 months, which is the better option? Explain. Green Lawn; for 6 months. Green Lawns service costs only $223, while Grass Team's costs $247.

p.340: 17 Casey wants to buy a gym membership. One gym has a $150 joining fee and costs $35 per month. Another gym has no joining fee and costs $60 per month. a. In how many months will both gym memberships cost the same? What will that cost be? 6 months; $360 b. If Casey plans to cancel in 5 months, which is the better option for him? Explain. The second option; for 5 months. It costs only $300, while the other option costs $325.

p.341: 24 Justin and Lacee are taking a walk. Justin walks at a rate of 6 ft/s, while Lacee walks at 4 ft/s. Lacee starts 10 ft ahead of Justin. a. After how many seconds will Lacee and Justin be next to each other? What will that distance be? 5 s; 30 ft b. How many seconds will it take for Justin to catch up to Lacee if she starts 32 ft ahead of Justin? 16s

p.341: 27 Helene invested a total of $1000 in two simple interest bank accounts. One account paid 5% annual interest; the other paid 6% annual interest. The total amount of interest she earned after one year was $58. Write and solve a system of equations to find the amount invested in each account. x + y = 1000 $200 at 5% 0.05x + 0.06y = 58 $800 at 6%

a. How many calls did Tricia make last month? Michael? 20; 32 p.341: 32 Tricia and Michael share a cell phone plan. Together, they made a total of 52 calls last month for a total of 620 min. Tricia averaged 15 min for each of her calls, while Michael averaged 10 mins. a. How many calls did Tricia make last month? Michael? 20; 32 b. How many calls did Tricia make if the total number of calls was 60?

b. Solve the system by substitution. book $6; backpack $14 At a school store, Juanita bought 2 books and a backpack for a total of $26 before tax. Each book cost $8 less than the backpack. a. Write a system of equations that can be used to find the price of each book and the price of the backpack. 2x + y = 26 x = y - 8 b. Solve the system by substitution. book $6; backpack $14 c. Solve this system by graphing. Discuss advantages and disadvantages of solving by substitution and solving by graphing. x is already isolated so substitution works well.