1. Solve the system of equations x + y + z = 9, -x + y + z = 1, and x y z = 5. A. There is no solution. B. There are infinitely many solutions. C. There is not enough information to solve the problem. D. There is one solution, x = 4, y = 2, and z = 3. 2. Find the equation of the boundary line in the graph below. Then give the inequality represented by the shaded area. A. B. C. D. 3. When solving a system of equations using Cramer's Rule, if Dx = 0, Dy = -1, Dz = 1, and D = 0, then what can you conclude? A. The system is dependent. B. The system is inconsistent. C. The system has one solution, (0, 0, 0). D. The system has one solution, (0, -1, 1). 4. Choose the correct ways to fill in the blanks in the following sentence. To solve a system of equations using the matrix method, use __________ to transform the augmented matrix into one with __________, then proceed to back-substitute. A. multiplication and addition, zeros in its final column B. the coefficient matrix, an inverse C. the coefficient matrix, Gaussian elimination D. elementary row operations, zeros below the diagonal 6. The matrix below is the augmented matrix of a system of three equations in the variables x and y. Solve for x and y. A. One solution, B. One solution (0, 9) C. No solution D. Infinitely many solutions 7. Solve the inequality . 3 < or equal to 4 =3x/2 < or equal to 2.Give the result in set notation and graph it. A. B. C. D. 8. If the edge isn't included in the graph of an inequality, you should draw it as a/an _______ line. A. closed B. open C. solid D. dashed 10. Find the value of the expression -|-18|. A. 18 B. -18 C. 0 D. Undefined 11. Solve the inequality -2 (3 + x) < 4x + 4 < 8x. Give the result in set notation and graph it. A. B. C. D. : 13. Solve the inequality . Give the result in set notation and graph it. A. B. C. D. Student Answer: B Answer: Incorrect 14. Solve the system of equations 2x y + z = -7, x 3y + 4z = -19, and -x + 4y 3z = 18. A. There is one solution, (1, 2, 3). B. There is one solution, (-1, -2, -3). C. There is one solution, (1, -2, 3). D. There is one solution, (-1, 2, -3). 20. Solve the inequality |5x + 10| 15. Write the solution in interval notation and graph it. A. B. C. D. 23. Solve the system of equations 2x 2y 2z = 3, x + 4y z = 2, and -2x 8y + 2z = -4. A. There is no solution. B. There are infinitely many solutions, of the form (0.1, 0.1, -1.5). C. There are infinitely many solutions, of the form (x, 0.1, x 1.6). D. There is one solution, (0.1, 0.1, -1.5). 25. What is the formula for the determinant of a 3 x 3 matrix ? A. B. C. D