← Algebraic identities lesson New set →

Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 304 · 40 sums
TalentJR

The method (Split into easy parts): (a + b)² = a² + 2ab + b². (a − b)² = a² − 2ab + b². (a + b)(a − b) = a² − b²; so a² − b² = (a + b)(a − b). a² + b² = (a + b)² − 2ab = (a − b)² + 2ab.

NameDateTime takenScore ___ / 40
  1. 1.If a − b = 1 and ab = 30, what is a² + b²?
  2. 2.Use (a − b)² = a² − 2ab + b² to find 35².
  3. 3.Find the value of x² + 2xy + y² when x = 5 and y = 4.
  4. 4.If a − b = 1 and ab = 2, what is a² + b²?
  5. 5.Use a² − b² = (a + b)(a − b) to find 42² − 9².
  6. 6.Use (a + b)(a − b) = a² − b² to find 21 × 19.
  7. 7.If a + b = 4 and ab = 3, what is a² + b²?
  8. 8.Use (a + b)² = a² + 2ab + b² to find 103².
  9. 9.Use (a + b)² = a² + 2ab + b² to find 53².
  10. 10.Use a² − b² = (a + b)(a − b) to find 34² − 31².
  11. 11.Use a² − b² = (a + b)(a − b) to find 70² − 19².
  12. 12.Use (a + b)(a − b) = a² − b² to find 33 × 27.
  13. 13.Use (a + b)(a − b) = a² − b² to find 34 × 26.
  14. 14.Find the value of x² + 2xy + y² when x = 9 and y = 8.
  15. 15.If a − b = 4 and ab = 21, what is a² + b²?
  16. 16.Find the value of x² + 2xy + y² when x = 4 and y = 1.
  17. 17.Find the value of x² − 2xy + y² when x = 4 and y = 3.
  18. 18.Use a² − b² = (a + b)(a − b) to find 92² − 3².
  19. 19.If a − b = 1 and ab = 12, what is a² + b²?
  20. 20.If a + b = 13 and ab = 22, what is a² + b²?
  21. 21.Use (a + b)² = a² + 2ab + b² to find 29².
  22. 22.Use (a + b)(a − b) = a² − b² to find 25 × 15.
  23. 23.Use a² − b² = (a + b)(a − b) to find 60² − 58².
  24. 24.Find the value of x² − 2xy + y² when x = 6 and y = 4.
  25. 25.Use (a + b)(a − b) = a² − b² to find 71 × 69.
  26. 26.Use (a + b)² = a² + 2ab + b² to find 21².
  27. 27.Use (a + b)² = a² + 2ab + b² to find 45².
  28. 28.Use (a − b)² = a² − 2ab + b² to find 17².
  29. 29.Use a² − b² = (a + b)(a − b) to find 69² − 46².
  30. 30.Use (a + b)(a − b) = a² − b² to find 29 × 11.
  31. 31.Use a² − b² = (a + b)(a − b) to find 97² − 66².
  32. 32.Use a² − b² = (a + b)(a − b) to find 65² − 12².
  33. 33.Use (a + b)(a − b) = a² − b² to find 36 × 24.
  34. 34.Use (a + b)² = a² + 2ab + b² to find 107².
  35. 35.Find the value of x² + 2xy + y² when x = 3 and y = 2.
  36. 36.If a + b = 3 and ab = 2, what is a² + b²?
  37. 37.Use a² − b² = (a + b)(a − b) to find 48² − 29².
  38. 38.Use (a + b)² = a² + 2ab + b² to find 59².
  39. 39.Use (a − b)² = a² − 2ab + b² to find 18².
  40. 40.Use a² − b² = (a + b)(a − b) to find 52² − 26².

Answer key

  1. 61
  2. 1225
  3. 81
  4. 5
  5. 1683
  6. 399
  7. 10
  8. 10609
  9. 2809
  10. 195
  11. 4539
  12. 891
  13. 884
  14. 289
  15. 58
  16. 25
  17. 1
  18. 8455
  19. 25
  20. 125
  21. 841
  22. 375
  23. 236
  24. 4
  25. 4899
  26. 441
  27. 2025
  28. 289
  29. 2645
  30. 319
  31. 5053
  32. 4081
  33. 864
  34. 11449
  35. 25
  36. 5
  37. 1463
  38. 3481
  39. 324
  40. 2028

Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets