Grade 8 Math Worksheet: Solve for x in each of the following equations.
Grade 8 mathematics worksheet with ten algebraic equations to solve for x, labeled "Additional Material" at the top.
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Step-by-step solution for: GRADE 8 +9 MATH WORKSHEETS - Like terms and solving linear ...
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Show Answer Key & Explanations
Step-by-step solution for: GRADE 8 +9 MATH WORKSHEETS - Like terms and solving linear ...
Of course! I'll solve each of the 10 equations for `x` step by step and explain the process clearly. These are all linear equations, so we’ll use inverse operations to isolate `x`.
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1. 2x + 5 = 17
Goal: Get `x` alone on one side.
- Subtract 5 from both sides:
> 2x = 17 - 5
> 2x = 12
- Divide both sides by 2:
> x = 12 ÷ 2
> x = 6
✔ Answer: x = 6
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2. 3(x - 4) = 15
Goal: Distribute first, then isolate `x`.
- Distribute the 3:
> 3x - 12 = 15
- Add 12 to both sides:
> 3x = 15 + 12
> 3x = 27
- Divide by 3:
> x = 27 ÷ 3
> x = 9
✔ Answer: x = 9
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3. 4x - 7 = 3x + 11
Goal: Get all `x` terms on one side, constants on the other.
- Subtract 3x from both sides:
> 4x - 3x - 7 = 11
> x - 7 = 11
- Add 7 to both sides:
> x = 11 + 7
> x = 18
✔ Answer: x = 18
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4. 5(2x + 1) = 25 - x
Goal: Distribute, then collect like terms.
- Distribute the 5:
> 10x + 5 = 25 - x
- Add x to both sides (to move all x’s left):
> 10x + x + 5 = 25
> 11x + 5 = 25
- Subtract 5 from both sides:
> 11x = 20
- Divide by 11:
> x = 20/11
✔ Answer: x = 20/11 (or approximately 1.818...)
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5. 3x - 4 = 5 - 2x
Goal: Move variables to one side, constants to the other.
- Add 2x to both sides:
> 3x + 2x - 4 = 5
> 5x - 4 = 5
- Add 4 to both sides:
> 5x = 9
- Divide by 5:
> x = 9/5
✔ Answer: x = 9/5 (or 1.8)
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6. 2(3x - 1) + 5x = 13
Goal: Distribute, combine like terms, then solve.
- Distribute the 2:
> 6x - 2 + 5x = 13
- Combine like terms:
> 11x - 2 = 13
- Add 2 to both sides:
> 11x = 15
- Divide by 11:
> x = 15/11
✔ Answer: x = 15/11 (approximately 1.364...)
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7. 2(x + 3) - 5(x - 2) = 3
Goal: Distribute carefully, combine like terms.
- Distribute:
> 2x + 6 - 5x + 10 = 3
*(Note: -5 times -2 is +10)*
- Combine like terms:
> (2x - 5x) + (6 + 10) = 3
> -3x + 16 = 3
- Subtract 16 from both sides:
> -3x = 3 - 16
> -3x = -13
- Divide by -3:
> x = 13/3
✔ Answer: x = 13/3 (or 4 1/3)
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8. 3(x - 1) + 2(2x + 1) = 11
Goal: Distribute, combine, solve.
- Distribute:
> 3x - 3 + 4x + 2 = 11
*(2 × 2x = 4x; 2 × 1 = 2)*
- Combine like terms:
> (3x + 4x) + (-3 + 2) = 11
> 7x - 1 = 11
- Add 1 to both sides:
> 7x = 12
- Divide by 7:
> x = 12/7
✔ Answer: x = 12/7 (approximately 1.714...)
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9. 2x - 1 = x + 5
Goal: Move x terms to one side.
- Subtract x from both sides:
> 2x - x - 1 = 5
> x - 1 = 5
- Add 1 to both sides:
> x = 6
✔ Answer: x = 6
---
10. 5(x + 3) - 3(x - 1) = 22
Goal: Distribute, combine, solve.
- Distribute:
> 5x + 15 - 3x + 3 = 22
*(Note: -3 times -1 is +3)*
- Combine like terms:
> (5x - 3x) + (15 + 3) = 22
> 2x + 18 = 22
- Subtract 18 from both sides:
> 2x = 4
- Divide by 2:
> x = 2
✔ Answer: x = 2
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## ✔ Final Answers Summary:
1. x = 6
2. x = 9
3. x = 18
4. x = 20/11
5. x = 9/5
6. x = 15/11
7. x = 13/3
8. x = 12/7
9. x = 6
10. x = 2
Let me know if you’d like to see any of these explained in more detail or want to check your own work!
---
1. 2x + 5 = 17
Goal: Get `x` alone on one side.
- Subtract 5 from both sides:
> 2x = 17 - 5
> 2x = 12
- Divide both sides by 2:
> x = 12 ÷ 2
> x = 6
✔ Answer: x = 6
---
2. 3(x - 4) = 15
Goal: Distribute first, then isolate `x`.
- Distribute the 3:
> 3x - 12 = 15
- Add 12 to both sides:
> 3x = 15 + 12
> 3x = 27
- Divide by 3:
> x = 27 ÷ 3
> x = 9
✔ Answer: x = 9
---
3. 4x - 7 = 3x + 11
Goal: Get all `x` terms on one side, constants on the other.
- Subtract 3x from both sides:
> 4x - 3x - 7 = 11
> x - 7 = 11
- Add 7 to both sides:
> x = 11 + 7
> x = 18
✔ Answer: x = 18
---
4. 5(2x + 1) = 25 - x
Goal: Distribute, then collect like terms.
- Distribute the 5:
> 10x + 5 = 25 - x
- Add x to both sides (to move all x’s left):
> 10x + x + 5 = 25
> 11x + 5 = 25
- Subtract 5 from both sides:
> 11x = 20
- Divide by 11:
> x = 20/11
✔ Answer: x = 20/11 (or approximately 1.818...)
---
5. 3x - 4 = 5 - 2x
Goal: Move variables to one side, constants to the other.
- Add 2x to both sides:
> 3x + 2x - 4 = 5
> 5x - 4 = 5
- Add 4 to both sides:
> 5x = 9
- Divide by 5:
> x = 9/5
✔ Answer: x = 9/5 (or 1.8)
---
6. 2(3x - 1) + 5x = 13
Goal: Distribute, combine like terms, then solve.
- Distribute the 2:
> 6x - 2 + 5x = 13
- Combine like terms:
> 11x - 2 = 13
- Add 2 to both sides:
> 11x = 15
- Divide by 11:
> x = 15/11
✔ Answer: x = 15/11 (approximately 1.364...)
---
7. 2(x + 3) - 5(x - 2) = 3
Goal: Distribute carefully, combine like terms.
- Distribute:
> 2x + 6 - 5x + 10 = 3
*(Note: -5 times -2 is +10)*
- Combine like terms:
> (2x - 5x) + (6 + 10) = 3
> -3x + 16 = 3
- Subtract 16 from both sides:
> -3x = 3 - 16
> -3x = -13
- Divide by -3:
> x = 13/3
✔ Answer: x = 13/3 (or 4 1/3)
---
8. 3(x - 1) + 2(2x + 1) = 11
Goal: Distribute, combine, solve.
- Distribute:
> 3x - 3 + 4x + 2 = 11
*(2 × 2x = 4x; 2 × 1 = 2)*
- Combine like terms:
> (3x + 4x) + (-3 + 2) = 11
> 7x - 1 = 11
- Add 1 to both sides:
> 7x = 12
- Divide by 7:
> x = 12/7
✔ Answer: x = 12/7 (approximately 1.714...)
---
9. 2x - 1 = x + 5
Goal: Move x terms to one side.
- Subtract x from both sides:
> 2x - x - 1 = 5
> x - 1 = 5
- Add 1 to both sides:
> x = 6
✔ Answer: x = 6
---
10. 5(x + 3) - 3(x - 1) = 22
Goal: Distribute, combine, solve.
- Distribute:
> 5x + 15 - 3x + 3 = 22
*(Note: -3 times -1 is +3)*
- Combine like terms:
> (5x - 3x) + (15 + 3) = 22
> 2x + 18 = 22
- Subtract 18 from both sides:
> 2x = 4
- Divide by 2:
> x = 2
✔ Answer: x = 2
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## ✔ Final Answers Summary:
1. x = 6
2. x = 9
3. x = 18
4. x = 20/11
5. x = 9/5
6. x = 15/11
7. x = 13/3
8. x = 12/7
9. x = 6
10. x = 2
Let me know if you’d like to see any of these explained in more detail or want to check your own work!
Parent Tip: Review the logic above to help your child master the concept of expressions and equations worksheet 8th grade.