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9th Grade Factoring Expressions (Common Factors) Worksheet — Level 3 — Practice Set 3 — Answers

Answer sheet with worked solutions for the 9th Grade algebraic expressions worksheet.

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Success TutoringWorksheetsAnswer sheet9th Grade · Mathematics · Algebraic Expressions

9th Grade Factoring Expressions (Common Factors) Worksheet — Level 3 — Practice Set 3 — Answers

Take out the highest common factor. Where the first term is negative, take out a negative factor.

1.Factor fully: −18x − 21

Answer: −3(6x + 7)

  1. Highest common factor: −3
  2. −18x − 21 = −3(6x + 7)
  3. Check by expanding the parentheses.
2.Factor fully: 24x2 − 18x − 12

Answer: 6(4x2−3x−2)

  1. Highest common factor: 6
  2. 24x2 − 18x − 12 = 6(4x2 − 3x − 2)
  3. Check by expanding the parentheses.
3.Factor fully: 30ab + 42a

Answer: 6a(5b + 7)

  1. Highest common factor: 6a
  2. 30ab + 42a = 6a(5b + 7)
  3. Check by expanding the parentheses.
4.Factor fully: −6x − 14

Answer: −2(3x + 7)

  1. Highest common factor: −2
  2. −6x − 14 = −2(3x + 7)
  3. Check by expanding the parentheses.
5.Factor fully: 6x2 − 18x + 48

Answer: 6(x2−3x+8)

  1. Highest common factor: 6
  2. 6x2 − 18x + 48 = 6(x2 − 3x + 8)
  3. Check by expanding the parentheses.
6.Factor fully: 15ab + 40a

Answer: 5a(3b + 8)

  1. Highest common factor: 5a
  2. 15ab + 40a = 5a(3b + 8)
  3. Check by expanding the parentheses.
7.Factor fully: −2x − 16

Answer: −2(x + 8)

  1. Highest common factor: −2
  2. −2x − 16 = −2(x + 8)
  3. Check by expanding the parentheses.
8.Factor fully: 10x2 − 5x + 40

Answer: 5(2x2−x+8)

  1. Highest common factor: 5
  2. 10x2 − 5x + 40 = 5(2x2 − x + 8)
  3. Check by expanding the parentheses.
9.Factor fully: 6ab + 42a

Answer: 6a(b + 7)

  1. Highest common factor: 6a
  2. 6ab + 42a = 6a(b + 7)
  3. Check by expanding the parentheses.
10.Factor fully: −12x − 3

Answer: −3(4x + 1)

  1. Highest common factor: −3
  2. −12x − 3 = −3(4x + 1)
  3. Check by expanding the parentheses.
11.Factor fully: 3x2 − 18x + 3

Answer: 3(x2−6x+1)

  1. Highest common factor: 3
  2. 3x2 − 18x + 3 = 3(x2 − 6x + 1)
  3. Check by expanding the parentheses.
12.Factor fully: 4ab − 16a

Answer: 4a(b − 4)

  1. Highest common factor: 4a
  2. 4ab − 16a = 4a(b − 4)
  3. Check by expanding the parentheses.
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