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MathsAges 10-12

Missing-value equations

Find the missing value that makes an equation true, then check by substitution. Review suitability for your learners before teaching.

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Age band:Ages 7-9Ages 10-12

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Worksheet StudioPractice pack · Ages 10-12

Missing-value equations

Take your time. Show your thinking.

  1. 1. 9 × x + 3 = 84. Find x.

    LHS=RHS
    9 · 3 · 84 · Missing-value equations

  2. 2. 12 × x + 19 = 163. Find x.

    LHS=RHS
    12 · 19 · 163 · Missing-value equations

  3. 3. 5 × x + 17 = 42. Find x.

    LHS=RHS
    5 · 17 · 42 · Missing-value equations

  4. 4. 4 × x + 9 = 25. Find x.

    LHS=RHS
    4 · 9 · 25 · Missing-value equations

  5. 5. 10 × x + 4 = 104. Find x.

    LHS=RHS
    10 · 4 · 104 · Missing-value equations

  6. 6. 3 × x + 20 = 29. Find x.

    LHS=RHS
    3 · 20 · 29 · Missing-value equations

  7. 7. 5 × x + 2 = 27. Find x.

    LHS=RHS
    5 · 2 · 27 · Missing-value equations

  8. 8. 3 × x + 9 = 18. Find x.

    LHS=RHS
    3 · 9 · 18 · Missing-value equations

  9. 9. 7 × x + 16 = 65. Find x.

    LHS=RHS
    7 · 16 · 65 · Missing-value equations

  10. 10. 3 × x + 6 = 15. Find x.

    LHS=RHS
    3 · 6 · 15 · Missing-value equations

  11. 11. 12 × x + 13 = 157. Find x.

    LHS=RHS
    12 · 13 · 157 · Missing-value equations

  12. 12. 3 × x + 16 = 25. Find x.

    LHS=RHS
    3 · 16 · 25 · Missing-value equations
12 questions · Seed 104730 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 10-12

Missing-value equations

Answers and reasoning. Review before teaching.

  1. 1. 9 × x + 3 = 84. Find x.

    9

    Subtract 3, then divide by 9: x = 9.

  2. 2. 12 × x + 19 = 163. Find x.

    12

    Subtract 19, then divide by 12: x = 12.

  3. 3. 5 × x + 17 = 42. Find x.

    5

    Subtract 17, then divide by 5: x = 5.

  4. 4. 4 × x + 9 = 25. Find x.

    4

    Subtract 9, then divide by 4: x = 4.

  5. 5. 10 × x + 4 = 104. Find x.

    10

    Subtract 4, then divide by 10: x = 10.

  6. 6. 3 × x + 20 = 29. Find x.

    3

    Subtract 20, then divide by 3: x = 3.

  7. 7. 5 × x + 2 = 27. Find x.

    5

    Subtract 2, then divide by 5: x = 5.

  8. 8. 3 × x + 9 = 18. Find x.

    3

    Subtract 9, then divide by 3: x = 3.

  9. 9. 7 × x + 16 = 65. Find x.

    7

    Subtract 16, then divide by 7: x = 7.

  10. 10. 3 × x + 6 = 15. Find x.

    3

    Subtract 6, then divide by 3: x = 3.

  11. 11. 12 × x + 13 = 157. Find x.

    12

    Subtract 13, then divide by 12: x = 12.

  12. 12. 3 × x + 16 = 25. Find x.

    3

    Subtract 16, then divide by 3: x = 3.

12 questions · Seed 104730 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12

Missing-value equations

Take your time. Show your thinking.

  1. 1. 9 × x + 3 = 84. Find x.

    LHS=RHS
    9 · 3 · 84 · Missing-value equations

  2. 2. 12 × x + 19 = 163. Find x.

    LHS=RHS
    12 · 19 · 163 · Missing-value equations

  3. 3. 5 × x + 17 = 42. Find x.

    LHS=RHS
    5 · 17 · 42 · Missing-value equations

  4. 4. 4 × x + 9 = 25. Find x.

    LHS=RHS
    4 · 9 · 25 · Missing-value equations

  5. 5. 10 × x + 4 = 104. Find x.

    LHS=RHS
    10 · 4 · 104 · Missing-value equations

  6. 6. 3 × x + 20 = 29. Find x.

    LHS=RHS
    3 · 20 · 29 · Missing-value equations

  7. 7. 5 × x + 2 = 27. Find x.

    LHS=RHS
    5 · 2 · 27 · Missing-value equations

  8. 8. 3 × x + 9 = 18. Find x.

    LHS=RHS
    3 · 9 · 18 · Missing-value equations

  9. 9. 7 × x + 16 = 65. Find x.

    LHS=RHS
    7 · 16 · 65 · Missing-value equations

  10. 10. 3 × x + 6 = 15. Find x.

    LHS=RHS
    3 · 6 · 15 · Missing-value equations

  11. 11. 12 × x + 13 = 157. Find x.

    LHS=RHS
    12 · 13 · 157 · Missing-value equations

  12. 12. 3 × x + 16 = 25. Find x.

    LHS=RHS
    3 · 16 · 25 · Missing-value equations
12 questions · Seed 104730 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12

Missing-value equations

Answers and reasoning. Review before teaching.

  1. 1. 9 × x + 3 = 84. Find x.

    9

    Subtract 3, then divide by 9: x = 9.

  2. 2. 12 × x + 19 = 163. Find x.

    12

    Subtract 19, then divide by 12: x = 12.

  3. 3. 5 × x + 17 = 42. Find x.

    5

    Subtract 17, then divide by 5: x = 5.

  4. 4. 4 × x + 9 = 25. Find x.

    4

    Subtract 9, then divide by 4: x = 4.

  5. 5. 10 × x + 4 = 104. Find x.

    10

    Subtract 4, then divide by 10: x = 10.

  6. 6. 3 × x + 20 = 29. Find x.

    3

    Subtract 20, then divide by 3: x = 3.

  7. 7. 5 × x + 2 = 27. Find x.

    5

    Subtract 2, then divide by 5: x = 5.

  8. 8. 3 × x + 9 = 18. Find x.

    3

    Subtract 9, then divide by 3: x = 3.

  9. 9. 7 × x + 16 = 65. Find x.

    7

    Subtract 16, then divide by 7: x = 7.

  10. 10. 3 × x + 6 = 15. Find x.

    3

    Subtract 6, then divide by 3: x = 3.

  11. 11. 12 × x + 13 = 157. Find x.

    12

    Subtract 13, then divide by 12: x = 12.

  12. 12. 3 × x + 16 = 25. Find x.

    3

    Subtract 16, then divide by 3: x = 3.

12 questions · Seed 104730 · Age guidance, not curriculum certification