1. Homework for 7-4 p. 454 2, 4, 7, 10, 17, 20, 25, 32, 38, 43, 48, 52

2. 7-4 Solve Linear Systems by Multiplying First Objective: solve linear systems by elimination using multiplication first

3. Concessions A concession stand offers two different soft drink specials. One special has 3 large drinks and 2 medium drinks for $15. The other has 2 large drinks and 3 medium drinks for $13.75. Write a system of linear equations to determine the cost of each drink size. 3g + 2m = 15 2g + 3m = 13.75 Can this system be solved using graphing? Substitution? Elimination by +/-?

4. Solve Using Multiplication First 2x + y = -9 4x + 11y = 9 y = 3 2x + (3) = -9 2x = -12 x = -6 Solution is (-6, 3) What would you need to multiply by to eliminate y instead of x? x (-2) -4x - 2y = 18 4x + 11y = 9 9y = 27

5. Solve the Linear System 2x – 3y = 6 4y = -7x – 8 Put in standard form: 2x – 3y = 6 7x + 4y = -8 What do we need to multiply by? Go ahead and solve! Solution is (0, -2)

6. Solve the Concessions Problem 3g + 2m = 15 2g + 3m = 13.75 -6g – 4m = -30 6g + 9m = 41.25 5m = 11.25 m = 2.25 g = 3.5 The large drinks cost $3.50; the mediums cost $2.25.

7. Multiple Choice Mr. Alvarez bought a total of 20 pounds of grass seed at the nursery for $168. He paid $9 per pound for Kentucky bluegrass (k) and $6 per pound for Tall Fescue (f). Which system of equations can be used to find the amount of each that Mr. Alvarez purchased? A.k + f = 168C. k + f = 168 9k + 6f = 20 6k + 9f = 20 B.k + f = 20D. k + f = 20 6k + 9f = 168 9k + 6f = 168 Answer: D