In Exercises 1-3, solve the system by the method of substitution. Check your solution graphically. 1. x - y=6 2. [ y = x - 1 3. [4x - 12 = 7 3x + 5y = 2 y = (x - 1)3 x - y = 3 In Exercises 4-6, solve the system by the method of elimination. 4. [2x + 5y = -11 5. [3x - 2y + = = 0 x - 4y - := 3 5x - y = 19 6x + 2y + 3z = -2 2x - 5y + z = 0 3x - 4y + 5z = 5 3x - 3y + 2z = -1 7. Find the equation of the parabola y = ax + bx + c that passes through the points (0, 6), (-2, 2), and (3, 7). In Exercises 8 and 9, write the partial fraction decomposition for the rational expression. -2x + 2y + 3z = 7 8. 5x - 2 g x txtx + 2 x - y -5 (x - 1)2 *+ x2 y + 4z = -1 In Exercises 10 and 11, use matrices to solve the system of equations, if possible. System for 13 10. [2x + y + 2z = 4 11. [2x + 3y + z = 10 2x + 2y = 5 2x - 3y - 3z = 22 2x - y + 62 = 2 (4x - 2y + 3z = -2 12- (4, 11) 10- 12. If possible, find (a) A - B, (b) 3A. (c) 3A - 2B, and (d) AB. 8- 4 6- B = 3 (4, 5) 2 4 - 2 (-1, 1)/ -8 - 6 -4 -2 / 2 4 6 -+ 6 8 13. Find A-' for A = 0 and use A-1 to solve the system at the right. (-1, -5) -6+ In Exercises 14 and 15, find the determinant of the matrix. Figure for 16 14. -28 191 *1 400 - 600 16. Use determinants to find the area of the parallelogram shown at the right. X2 X4 17. Use Cramer's Rule to solve (if possible) , 2X - 2y = 3 x + 4y = -1' 300 - 100 18. The flow of traffic (in vehicles per hour) through a network of streets is shown at the X5 right. Solve the system for the traffic flow represented by x;, i = 1, 2, 3, 4, and 5. Figure for 18