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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. 10 × x + 19 = 119. Find x.

    LHS=RHS
    10 · 19 · 119 · Missing-value equations

  2. 2. 10 × x + 18 = 118. Find x.

    LHS=RHS
    10 · 18 · 118 · Missing-value equations

  3. 3. 7 × x + 14 = 63. Find x.

    LHS=RHS
    7 · 14 · 63 · Missing-value equations

  4. 4. 5 × x + 7 = 32. Find x.

    LHS=RHS
    5 · 7 · 32 · Missing-value equations

  5. 5. 5 × x + 15 = 40. Find x.

    LHS=RHS
    5 · 15 · 40 · Missing-value equations

  6. 6. 12 × x + 14 = 158. Find x.

    LHS=RHS
    12 · 14 · 158 · Missing-value equations

  7. 7. 4 × x + 13 = 29. Find x.

    LHS=RHS
    4 · 13 · 29 · Missing-value equations

  8. 8. 12 × x + 7 = 151. Find x.

    LHS=RHS
    12 · 7 · 151 · Missing-value equations

  9. 9. 11 × x + 7 = 128. Find x.

    LHS=RHS
    11 · 7 · 128 · Missing-value equations

  10. 10. 3 × x + 7 = 16. Find x.

    LHS=RHS
    3 · 7 · 16 · Missing-value equations

  11. 11. 10 × x + 10 = 110. Find x.

    LHS=RHS
    10 · 10 · 110 · Missing-value equations

  12. 12. 11 × x + 3 = 124. Find x.

    LHS=RHS
    11 · 3 · 124 · Missing-value equations
12 questions · Seed 104732 · 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. 10 × x + 19 = 119. Find x.

    10

    Subtract 19, then divide by 10: x = 10.

  2. 2. 10 × x + 18 = 118. Find x.

    10

    Subtract 18, then divide by 10: x = 10.

  3. 3. 7 × x + 14 = 63. Find x.

    7

    Subtract 14, then divide by 7: x = 7.

  4. 4. 5 × x + 7 = 32. Find x.

    5

    Subtract 7, then divide by 5: x = 5.

  5. 5. 5 × x + 15 = 40. Find x.

    5

    Subtract 15, then divide by 5: x = 5.

  6. 6. 12 × x + 14 = 158. Find x.

    12

    Subtract 14, then divide by 12: x = 12.

  7. 7. 4 × x + 13 = 29. Find x.

    4

    Subtract 13, then divide by 4: x = 4.

  8. 8. 12 × x + 7 = 151. Find x.

    12

    Subtract 7, then divide by 12: x = 12.

  9. 9. 11 × x + 7 = 128. Find x.

    11

    Subtract 7, then divide by 11: x = 11.

  10. 10. 3 × x + 7 = 16. Find x.

    3

    Subtract 7, then divide by 3: x = 3.

  11. 11. 10 × x + 10 = 110. Find x.

    10

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

  12. 12. 11 × x + 3 = 124. Find x.

    11

    Subtract 3, then divide by 11: x = 11.

12 questions · Seed 104732 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12

Missing-value equations

Take your time. Show your thinking.

  1. 1. 10 × x + 19 = 119. Find x.

    LHS=RHS
    10 · 19 · 119 · Missing-value equations

  2. 2. 10 × x + 18 = 118. Find x.

    LHS=RHS
    10 · 18 · 118 · Missing-value equations

  3. 3. 7 × x + 14 = 63. Find x.

    LHS=RHS
    7 · 14 · 63 · Missing-value equations

  4. 4. 5 × x + 7 = 32. Find x.

    LHS=RHS
    5 · 7 · 32 · Missing-value equations

  5. 5. 5 × x + 15 = 40. Find x.

    LHS=RHS
    5 · 15 · 40 · Missing-value equations

  6. 6. 12 × x + 14 = 158. Find x.

    LHS=RHS
    12 · 14 · 158 · Missing-value equations

  7. 7. 4 × x + 13 = 29. Find x.

    LHS=RHS
    4 · 13 · 29 · Missing-value equations

  8. 8. 12 × x + 7 = 151. Find x.

    LHS=RHS
    12 · 7 · 151 · Missing-value equations

  9. 9. 11 × x + 7 = 128. Find x.

    LHS=RHS
    11 · 7 · 128 · Missing-value equations

  10. 10. 3 × x + 7 = 16. Find x.

    LHS=RHS
    3 · 7 · 16 · Missing-value equations

  11. 11. 10 × x + 10 = 110. Find x.

    LHS=RHS
    10 · 10 · 110 · Missing-value equations

  12. 12. 11 × x + 3 = 124. Find x.

    LHS=RHS
    11 · 3 · 124 · Missing-value equations
12 questions · Seed 104732 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12

Missing-value equations

Answers and reasoning. Review before teaching.

  1. 1. 10 × x + 19 = 119. Find x.

    10

    Subtract 19, then divide by 10: x = 10.

  2. 2. 10 × x + 18 = 118. Find x.

    10

    Subtract 18, then divide by 10: x = 10.

  3. 3. 7 × x + 14 = 63. Find x.

    7

    Subtract 14, then divide by 7: x = 7.

  4. 4. 5 × x + 7 = 32. Find x.

    5

    Subtract 7, then divide by 5: x = 5.

  5. 5. 5 × x + 15 = 40. Find x.

    5

    Subtract 15, then divide by 5: x = 5.

  6. 6. 12 × x + 14 = 158. Find x.

    12

    Subtract 14, then divide by 12: x = 12.

  7. 7. 4 × x + 13 = 29. Find x.

    4

    Subtract 13, then divide by 4: x = 4.

  8. 8. 12 × x + 7 = 151. Find x.

    12

    Subtract 7, then divide by 12: x = 12.

  9. 9. 11 × x + 7 = 128. Find x.

    11

    Subtract 7, then divide by 11: x = 11.

  10. 10. 3 × x + 7 = 16. Find x.

    3

    Subtract 7, then divide by 3: x = 3.

  11. 11. 10 × x + 10 = 110. Find x.

    10

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

  12. 12. 11 × x + 3 = 124. Find x.

    11

    Subtract 3, then divide by 11: x = 11.

12 questions · Seed 104732 · Age guidance, not curriculum certification