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Free · Class 8–10 · 5 worksheets · answer keys · practise online · set 26

Algebra formulas sheet — identities, with practice questions

Free algebra formulas sheet: (a + b)², (a − b)², (a + b)(a − b), (a + b)³ and more, with printable practice — expand, factorise and use identities to calculate, with answers.

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Expand the square (Class 8–9)(a + b)(a − b) (Class 8–9)Calculate with identities (Class 8–9)Factorise using identities (Class 9)Expand the cube (Class 9)

Expand the square

Class 8–9 · Worksheet 1 · set 26
Name:Date:Score:    / 10

Expand using (a + b)² or (a − b)².

  1. (4m + 2)²
  2. (4a − 3)²
  3. (3a − 1)²
  4. (5m − 1)²
  5. (2x + 9)²
  6. (2y + 7)²
  7. (2m + 9)²
  8. (5y + 4)²
  9. (4m − 4)²
  10. (y + 1)²

(a + b)(a − b)

Class 8–9 · Worksheet 2 · set 26
Name:Date:Score:    / 10

Multiply using (a + b)(a − b) = a² − b².

  1. (y + 7)(y − 7)
  2. (5x + 2)(5x − 2)
  3. (3y + 2)(3y − 2)
  4. (2y + 8)(2y − 8)
  5. (m + 5)(m − 5)
  6. (4y + 8)(4y − 8)
  7. (4m + 2)(4m − 2)
  8. (4a + 6)(4a − 6)
  9. (3x + 6)(3x − 6)
  10. (3m + 9)(3m − 9)

Calculate with identities

Class 8–9 · Worksheet 3 · set 26
Name:Date:Score:    / 10

Use an identity — no long multiplication.

  1. Use an identity to find 44²
  2. Use an identity to find 91²
  3. Use an identity to find 1001 × 999
  4. Use an identity to find 46 × 47
  5. Use an identity to find 48 × 49
  6. Use an identity to find 51²
  7. Use an identity to find 105 × 95
  8. Use an identity to find 42 × 43
  9. Use an identity to find 1005 × 995
  10. Use an identity to find 96 × 97

Factorise using identities

Class 9 · Worksheet 4 · set 26
Name:Date:Score:    / 10

Factorise.

  1. 4y² − 20y + 25
  2. 25x² − 40x + 16
  3. 25x² − 80x + 64
  4. m² − 36
  5. 4x² + 28x + 49
  6. 25m² + 30m + 9
  7. 25a² − 10a + 1
  8. 25y² + 60y + 36
  9. y² − 25
  10. 9y² + 12y + 4

Expand the cube

Class 9 · Worksheet 5 · set 26
Name:Date:Score:    / 8

Expand using (a + b)³.

  1. (x − 2)³
  2. (x + 5)³
  3. (x − 3)³
  4. (x + 3)³
  5. (x − 4)³
  6. (x − 5)³
  7. (x + 4)³
  8. (x + 1)³

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Questions

What are the basic algebraic identities?

(a + b)² = a² + 2ab + b², (a − b)² = a² − 2ab + b² and (a + b)(a − b) = a² − b² — learn these three first; the others build on them.

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Yes — print them or save as PDF free. Every worksheet has an answer key.

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Can my child do this worksheet online, like a quiz?

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