Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 999 · 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 26².
2. 2.Use (a + b)(a − b) = a² − b² to find 67 × 53.
3. 3.Use (a + b)² = a² + 2ab + b² to find 56².
4. 4.Use a² − b² = (a + b)(a − b) to find 26² − 8².
5. 5.Use (a − b)² = a² − 2ab + b² to find 38².
6. 6.Use (a + b)² = a² + 2ab + b² to find 82².
7. 7.If a − b = 3 and ab = 4, what is a² + b²?
8. 8.Use (a − b)² = a² − 2ab + b² to find 94².
9. 9.Use (a + b)(a − b) = a² − b² to find 93 × 87.
10. 10.Use (a + b)(a − b) = a² − b² to find 78 × 62.
11. 11.Use (a + b)² = a² + 2ab + b² to find 105².
12. 12.Use a² − b² = (a + b)(a − b) to find 45² − 20².
13. 13.Use a² − b² = (a + b)(a − b) to find 40² − 13².
14. 14.If a + b = 8 and ab = 12, what is a² + b²?
15. 15.If a + b = 18 and ab = 77, what is a² + b²?
16. 16.Use (a − b)² = a² − 2ab + b² to find 32².
17. 17.Use (a − b)² = a² − 2ab + b² to find 81².
18. 18.Use (a + b)² = a² + 2ab + b² to find 73².
19. 19.Use (a + b)² = a² + 2ab + b² to find 85².
20. 20.Use (a + b)² = a² + 2ab + b² to find 15².
21. 21.Use (a + b)(a − b) = a² − b² to find 43 × 37.
22. 22.Find the value of x² − 2xy + y² when x = 14 and y = 11.
23. 23.Find the value of x² − 2xy + y² when x = 15 and y = 7.
24. 24.Use (a + b)² = a² + 2ab + b² to find 39².
25. 25.Use (a + b)² = a² + 2ab + b² to find 72².
26. 26.Use (a + b)² = a² + 2ab + b² to find 22².
27. 27.Use (a + b)(a − b) = a² − b² to find 21 × 19.
28. 28.Use (a − b)² = a² − 2ab + b² to find 79².
29. 29.Use (a + b)² = a² + 2ab + b² to find 86².
30. 30.Use (a + b)² = a² + 2ab + b² to find 26².
31. 31.Use (a + b)² = a² + 2ab + b² to find 46².
32. 32.Use (a + b)² = a² + 2ab + b² to find 25².
33. 33.Use a² − b² = (a + b)(a − b) to find 25² − 22².
34. 34.Use (a − b)² = a² − 2ab + b² to find 68².
35. 35.Use (a − b)² = a² − 2ab + b² to find 45².
36. 36.Use a² − b² = (a + b)(a − b) to find 69² − 47².
37. 37.Use (a + b)² = a² + 2ab + b² to find 52².
38. 38.Use (a + b)(a − b) = a² − b² to find 26 × 14.
39. 39.Use (a + b)² = a² + 2ab + b² to find 92².
40. 40.If a − b = 1 and ab = 30, what is a² + b²?

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