Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 329 · 40 sums

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.

1. 1.Use (a − b)² = a² − 2ab + b² to find 66².
2. 2.Use (a − b)² = a² − 2ab + b² to find 24².
3. 3.Use (a − b)² = a² − 2ab + b² to find 52².
4. 4.Use (a + b)(a − b) = a² − b² to find 82 × 78.
5. 5.Use (a + b)(a − b) = a² − b² to find 24 × 16.
6. 6.Use (a + b)(a − b) = a² − b² to find 47 × 33.
7. 7.Use a² − b² = (a + b)(a − b) to find 69² − 14².
8. 8.If a + b = 17 and ab = 72, what is a² + b²?
9. 9.Use (a − b)² = a² − 2ab + b² to find 62².
10. 10.Use (a + b)² = a² + 2ab + b² to find 27².
11. 11.Use a² − b² = (a + b)(a − b) to find 35² − 20².
12. 12.If a − b = 2 and ab = 24, what is a² + b²?
13. 13.Use (a − b)² = a² − 2ab + b² to find 97².
14. 14.Use (a + b)² = a² + 2ab + b² to find 33².
15. 15.Use (a − b)² = a² − 2ab + b² to find 27².
16. 16.Use a² − b² = (a + b)(a − b) to find 31² − 12².
17. 17.Use a² − b² = (a + b)(a − b) to find 55² − 47².
18. 18.If a − b = 3 and ab = 40, what is a² + b²?
19. 19.Find the value of x² − y² when x = 6 and y = 3.
20. 20.Find the value of x² − 2xy + y² when x = 6 and y = 1.
21. 21.If a + b = 8 and ab = 15, what is a² + b²?
22. 22.Use (a + b)² = a² + 2ab + b² to find 26².
23. 23.Find the value of x² − y² when x = 11 and y = 7.
24. 24.Find the value of x² − y² when x = 9 and y = 7.
25. 25.Use (a + b)(a − b) = a² − b² to find 83 × 77.
26. 26.Find the value of x² − 2xy + y² when x = 14 and y = 5.
27. 27.Find the value of x² − y² when x = 8 and y = 4.
28. 28.If a − b = 7 and ab = 60, what is a² + b²?
29. 29.Find the value of x² + 2xy + y² when x = 5 and y = 2.
30. 30.Use (a + b)(a − b) = a² − b² to find 37 × 23.
31. 31.If a + b = 10 and ab = 24, what is a² + b²?
32. 32.If a + b = 7 and ab = 10, what is a² + b²?
33. 33.Find the value of x² − 2xy + y² when x = 13 and y = 12.
34. 34.Use (a − b)² = a² − 2ab + b² to find 57².
35. 35.Use (a + b)(a − b) = a² − b² to find 32 × 28.
36. 36.Use a² − b² = (a + b)(a − b) to find 28² − 22².
37. 37.If a + b = 13 and ab = 42, what is a² + b²?
38. 38.Use (a + b)(a − b) = a² − b² to find 72 × 68.
39. 39.Use (a − b)² = a² − 2ab + b² to find 69².
40. 40.If a + b = 3 and ab = 2, what is a² + b²?

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