Technical Mathematics, Sixth Edition

9.5. CHAPTER 9 REVIEW PROBLEMS

Solve each system of equations by any method.

1. 4x + 3y = 27

   2x − 5y = −19 (3, 5)

2. 

3. 

4. 2x + 4y − 3z = 22

   4x − 2y + 5z = 18

   6x + 7y − z = 63 (3, 7, 4)

5. 5x + 3y − 2z = 5

   3x − 4y + 3z = 13

   x + 6y − 4z = −8 (2, −1, 1)

6. 3x − 5y − 2z = 14

   5x − 8y − z = 12

   x − 3y − 3z = 1 (25, 15, −7)

7. 

8. 4x + 2y − 26 = 0

   3x + 4y = 39 (13/5, 39/5)

9. 2x − 3y + 14 = 0

   3x + 2y = 44 (8, 10)

10. 

11. 

12. 

13. x + y = a

    x + z = b

    y + z = c [(a + b − c)/2, (a − b + c)/2,(b − a + c)/2]

14. 

15. 

16. x + y + z = 35

    5x + 4y + 3z = 22

    3x + 4y − 3z = 2 (−86, 89, 32)

17. 2x − 4y + 3z = 10

    3x + y − 2z = 6

    x − 3y − z = 20 (1, −5, −4)

18. 5x + y − 4z = −5

    3x − 5y − 6z = −20

    x − 3y + 8z = −27 (−3, 4, −3/2)

19. x + 3y − z = 10

    5x − 2y + 2z = 6

    3x + 2y + z = 13 (2, 3, 1)

20. x + 21y = 2

    2x + 27y ...