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Grade 8 · Math · Unit 7 of 13

Equations with Brackets

Solve ax = b, x ÷ a = b, ax + b = c and a(x + b) = c

What your child practises

Solving one-variable equations, including ones with brackets and negative numbers, checking by substitution, and spotting a common mistake with the distributive property.

Alberta Curriculum learning outcome: PR2 · solving linear equations of the forms ax = b, x/a = b, ax + b = c and a(x + b) = c, and checking the solution

Sample questions

A taste of this unit. In the app, questions change every time and get easier or harder to match your child.

  1. Question 1

    Solve for x: x ÷ 8 = -3

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    -24

    Hint: Multiply both sides by 8: x = -3 × 8 = -24.

  2. Question 2

    Solve for x: 2(x + 6) = 18

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    3

    Hint: Divide both sides by 2: x + 6 = 9. Then subtract 6: x = 3. Check: 2(3 + 6) = 18.

  3. Question 3

    Which value of x makes 2x + 3 = 11 true?

    • 4
    • 3
    • 5
    • 6
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    4

    Hint: Substitute each value. Only x = 4 gives 2 × 4 + 3 = 11.

  4. Question 4

    Solve for x: 6(x − 2) = 42

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    9

    Hint: Divide both sides by 6: x − 2 = 7. Then add 2: x = 9. Check: 6(9 − 2) = 42.

  5. Question 5

    Solve for x: 2x − 2 = 8

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    5

    Hint: Undo the subtraction first: 2x = 10. Then divide by 2: x = 5.

  6. Question 6

    Solve for x: 6x = 12

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    2

    Hint: Divide both sides by 6: x = 12 ÷ 6 = 2.