Solving Linear Systems – Test Review 1. a) Graph each of the lines in the system of equations shown below and estimate the point of intersection. 4x + y + 1 = 0 3x - 2y = -8 b) c) 2. 3. 4. Solve the system using substitution (use fractions, not decimals!) Explain why there might be a difference between the two answers. Solve the following systems using substitution. a) x + 2y = 1 b) 3x - 4y = 32 x - 3y = 11 5x - y = 25 Solve the following systems using elimination. a) 5x - 2y = 10 b) 3a - b = 4 x + 2y = 2 a - 2b = 3 c) 2x + y = -8 10x - 3y - 16 = 0 c) 4x + 3y = 10 5x - 7y = -52 Solve the following systems using an algebraic method of your choice. a) 5v + u = -17 b) 3x + y = 2 3u - 4v = 6 6x - 3y + 16 = 0 c) 5x - 2y = -9 3x + 7y = 11 d) 4c - 5d = -2 8c + 10d = 8 5. White vinegar is a solution of acetic acid in water. There are two strengths of white vinegar – a 7% solution and a 12% solution. How many millilitres of each solution must be mixed to make 50 mL of a 10% vinegar solution? 6. A plane took 6 hours to fly 6300 km from Yukon to Halifax with a tail wind. The return trip, with a head wind, took 7 hours. Find the speed of the plane in still air and the wind speed. 7. Cindy and the Interact Club decided to hold a car wash to raise money. They washed cars for $5 each and vans for $7 each. They washed 45 vehicles and earned $275. How many of each type of vehicle did they wash? 8. Sarah took 7 hours to drive 550 km from Windsor to Peterborough. For part of the trip, she drove at 85 km/h and for the rest of the trip, drove at 70 km/h. How far did she drive at each speed? 9. Grace invested $6000, part at 5% per year and the rest at 8% per year. After one year, the total interest from these investments was $426. How much money did she invest at each rate? -------------------------------------------------------------------------------------------------Answers : 1b) (-10/11 ,29/11); 2a) (5, -2); b) (4, -5); c) (-½, -7); 3a) (2,0); b) (1,-1); c) (-2,6); 4a) (-2,-3); b) (- , 4); c) (-1,2); d) (¼, 3/5) 5) 20ml of 7% and 30ml of 12%; 6) plane speed is 975 km/h, wind speed is 75 km/h; 7) 20 cars & 25 vans; 8) 340km at 85km/h and 210km at 70km/h; 9) $1800 at 5% and $4200 at 8%