Systems: one, none or infinitely many solutions, and the quickest method

Grade 9 Math Worksheet - Challenge Me

NameDate

Circle the best answer, or write your answer on the line.

  1. Pia writes 2x + 3y = 12 and 4x + ky = 20. For which k does the system have no solution?

  2. Ren writes 3x + 4y = 10 and 6x + ky = 15. For which k does the system have no solution?

  3. Tala writes 2x + 5y = 7 and 6x + 15y = c. For which c does the system have infinitely many solutions?

  4. Zee writes 4x + 6y = 10 and 6x + ky = 15. For which k does the system have infinitely many solutions?

  5. Bo compares y = 3(x - 2) and y = 3x - 6. How many solutions does the system have?

    • One solution (independent)
    • No solution (inconsistent), since the two rules look different
    • Infinitely many solutions (dependent)
  6. Esme checks y = 2(x + 3) and y = 2x + 3. How many solutions does the system have?

    • Infinitely many solutions (dependent)
    • One solution (independent)
    • No solution (inconsistent)
  7. Kira reads 2(x + y) = 10 and x + y = 5. How many solutions does the system have?

    • No solution (inconsistent)
    • Infinitely many solutions (dependent)
    • One solution (independent)
  8. Read this first

    Old system

    x + 2y = 10 and x - y = 1. New system: -x + 4y = 8 and x - y = 1.

  9. Milo replaces the first equation with "first - 2 × second". The old solution is (4, 3). Which point solves the new system?

    • (8, 6)
    • (0, 2)
    • (3, 4)
    • (4, 3)
  10. Old system

    3x + 2y = 16 and 2x - y = 6. New system: 7x = 28 and 2x - y = 6.

  11. Noah replaces the first equation with "first + 2 × second". The old solution is (4, 2). Which point solves the new system?

    • (8, 4)
    • (2, 4)
    • (4, 2)
    • (4, 0)
  12. Old system

    x + 3y = 7 and 2x - y = 7. New system: -3x + 5y = -7 and 2x - y = 7.

  13. Pia replaces the first equation with "first - 2 × second". The old solution is (4, 1). Which point solves the new system?

    • (4, 1)
    • (8, 2)
    • (1, 4)
    • (-1, -2)
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Systems: one, none or infinitely many solutions, and the quickest method

Answer Key - Grade 9 Math Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.

  1. Pia writes 2x + 3y = 12 and 4x + ky = 20. For which k does the system have no solution?

    6
  2. Ren writes 3x + 4y = 10 and 6x + ky = 15. For which k does the system have no solution?

    8
  3. Tala writes 2x + 5y = 7 and 6x + 15y = c. For which c does the system have infinitely many solutions?

    21
  4. Zee writes 4x + 6y = 10 and 6x + ky = 15. For which k does the system have infinitely many solutions?

    9
  5. Bo compares y = 3(x - 2) and y = 3x - 6. How many solutions does the system have?

    • One solution (independent)
    • No solution (inconsistent), since the two rules look different
    • Infinitely many solutions (dependent)
  6. Esme checks y = 2(x + 3) and y = 2x + 3. How many solutions does the system have?

    • Infinitely many solutions (dependent)
    • One solution (independent)
    • No solution (inconsistent)
  7. Kira reads 2(x + y) = 10 and x + y = 5. How many solutions does the system have?

    • No solution (inconsistent)
    • Infinitely many solutions (dependent)
    • One solution (independent)
  8. Read this first

    Old system

    x + 2y = 10 and x - y = 1. New system: -x + 4y = 8 and x - y = 1.

  9. Milo replaces the first equation with "first - 2 × second". The old solution is (4, 3). Which point solves the new system?

    • (8, 6)
    • (0, 2)
    • (3, 4)
    • (4, 3)
  10. Old system

    3x + 2y = 16 and 2x - y = 6. New system: 7x = 28 and 2x - y = 6.

  11. Noah replaces the first equation with "first + 2 × second". The old solution is (4, 2). Which point solves the new system?

    • (8, 4)
    • (2, 4)
    • (4, 2)
    • (4, 0)
  12. Old system

    x + 3y = 7 and 2x - y = 7. New system: -3x + 5y = -7 and 2x - y = 7.

  13. Pia replaces the first equation with "first - 2 × second". The old solution is (4, 1). Which point solves the new system?

    • (4, 1)
    • (8, 2)
    • (1, 4)
    • (-1, -2)