← Algebraic identities lesson New set →

Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 497 · 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.Find the value of x² + 2xy + y² when x = 3 and y = 2.
  2. 2.Use a² − b² = (a + b)(a − b) to find 48² − 37².
  3. 3.Use (a + b)(a − b) = a² − b² to find 84 × 76.
  4. 4.Use (a + b)² = a² + 2ab + b² to find 61².
  5. 5.Use (a − b)² = a² − 2ab + b² to find 35².
  6. 6.Use (a + b)(a − b) = a² − b² to find 23 × 17.
  7. 7.Find the value of x² − y² when x = 13 and y = 1.
  8. 8.Use (a − b)² = a² − 2ab + b² to find 97².
  9. 9.Use (a − b)² = a² − 2ab + b² to find 65².
  10. 10.Use (a + b)² = a² + 2ab + b² to find 51².
  11. 11.Use a² − b² = (a + b)(a − b) to find 53² − 12².
  12. 12.Use (a + b)(a − b) = a² − b² to find 109 × 91.
  13. 13.Use (a + b)(a − b) = a² − b² to find 98 × 82.
  14. 14.Use (a + b)² = a² + 2ab + b² to find 29².
  15. 15.Use (a + b)(a − b) = a² − b² to find 71 × 69.
  16. 16.If a + b = 5 and ab = 4, what is a² + b²?
  17. 17.Use a² − b² = (a + b)(a − b) to find 82² − 17².
  18. 18.Find the value of x² + 2xy + y² when x = 7 and y = 5.
  19. 19.Use (a + b)(a − b) = a² − b² to find 97 × 83.
  20. 20.Use (a + b)(a − b) = a² − b² to find 83 × 77.
  21. 21.If a + b = 13 and ab = 12, what is a² + b²?
  22. 22.Use a² − b² = (a + b)(a − b) to find 49² − 45².
  23. 23.If a − b = 1 and ab = 2, what is a² + b²?
  24. 24.Use (a + b)² = a² + 2ab + b² to find 93².
  25. 25.Use (a + b)² = a² + 2ab + b² to find 87².
  26. 26.Use a² − b² = (a + b)(a − b) to find 36² − 8².
  27. 27.Find the value of x² − 2xy + y² when x = 13 and y = 9.
  28. 28.If a − b = 5 and ab = 66, what is a² + b²?
  29. 29.Use (a + b)(a − b) = a² − b² to find 53 × 47.
  30. 30.Find the value of x² − 2xy + y² when x = 7 and y = 2.
  31. 31.If a − b = 7 and ab = 30, what is a² + b²?
  32. 32.Find the value of x² + 2xy + y² when x = 4 and y = 3.
  33. 33.Use (a − b)² = a² − 2ab + b² to find 67².
  34. 34.Find the value of x² − y² when x = 4 and y = 1.
  35. 35.Find the value of x² − y² when x = 7 and y = 4.
  36. 36.Use a² − b² = (a + b)(a − b) to find 73² − 48².
  37. 37.Find the value of x² + 2xy + y² when x = 9 and y = 3.
  38. 38.Find the value of x² + 2xy + y² when x = 15 and y = 5.
  39. 39.Use (a − b)² = a² − 2ab + b² to find 38².
  40. 40.If a − b = 2 and ab = 63, what is a² + b²?

Answer key

  1. 25
  2. 935
  3. 6384
  4. 3721
  5. 1225
  6. 391
  7. 168
  8. 9409
  9. 4225
  10. 2601
  11. 2665
  12. 9919
  13. 8036
  14. 841
  15. 4899
  16. 17
  17. 6435
  18. 144
  19. 8051
  20. 6391
  21. 145
  22. 376
  23. 5
  24. 8649
  25. 7569
  26. 1232
  27. 16
  28. 157
  29. 2491
  30. 25
  31. 109
  32. 49
  33. 4489
  34. 15
  35. 33
  36. 3025
  37. 144
  38. 400
  39. 1444
  40. 130

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