1. Warm-Up: Problem of the Day Julie has dimes and quarters in her pocket. She has 24 coins in total. If the number of dimes is 3 less than twice the number of quarters, find the number of each type of coin. – Define 2 variables and write a system of equations to model this situation – Solve this system using substitution

2. Check Homework: #14. Let x be the speed of the plane; let y be the speed of the wind x + y = 300x – y = 200 #16. Let w be the width; Let l be the length 2w + 2l = 40l = w + 2 #17. Let x be the number mailed in N.A.; Let y be the number mailed outside N.A. x + y = 10400.46x + 0.48y = 483 # 18. Let m be money; let n be number of filters sold Cost: m = 1250 + 40nRevenue: m = 60n

3. Unit 1 Solving Linear Systems by Elimination Learning Goal: I can solve a system of linear equations algebraically, using the method of elimination

4. Solving by Elimination

5. Steps for Solving by Elimination 1)Match the numbers in front of x’s or y’s (may have to multiply one equation or both by a factor) 2)Eliminate one variable by adding or subtracting (elimination) 3)Solve for one variable 4)Substitute to find remaining variable 5)Check solution in opposite equation 6)State solution

6. Solving by Elimination

8. Homework Pg. 102 # 4, 6(a,c,e,g,i), 14 Solve all questions in #6 and 14 using elimination