Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 211 · 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 25².
2. 2.Use (a + b)² = a² + 2ab + b² to find 58².
3. 3.Use (a + b)(a − b) = a² − b² to find 77 × 63.
4. 4.Use (a + b)(a − b) = a² − b² to find 51 × 49.
5. 5.Use (a + b)(a − b) = a² − b² to find 67 × 53.
6. 6.Find the value of x² − 2xy + y² when x = 5 and y = 1.
7. 7.If a + b = 6 and ab = 5, what is a² + b²?
8. 8.Use a² − b² = (a + b)(a − b) to find 72² − 13².
9. 9.Use (a + b)² = a² + 2ab + b² to find 37².
10. 10.If a − b = 8 and ab = 9, what is a² + b²?
11. 11.Use (a + b)(a − b) = a² − b² to find 21 × 19.
12. 12.Use (a + b)² = a² + 2ab + b² to find 84².
13. 13.Find the value of x² − y² when x = 10 and y = 7.
14. 14.Use (a − b)² = a² − 2ab + b² to find 36².
15. 15.Use (a + b)(a − b) = a² − b² to find 58 × 42.
16. 16.Use a² − b² = (a + b)(a − b) to find 72² − 33².
17. 17.Find the value of x² − y² when x = 7 and y = 2.
18. 18.Find the value of x² − y² when x = 14 and y = 5.
19. 19.Use (a + b)² = a² + 2ab + b² to find 75².
20. 20.Use (a − b)² = a² − 2ab + b² to find 82².
21. 21.Use a² − b² = (a + b)(a − b) to find 21² − 19².
22. 22.Use (a + b)(a − b) = a² − b² to find 52 × 48.
23. 23.Use a² − b² = (a + b)(a − b) to find 38² − 10².
24. 24.Use (a + b)(a − b) = a² − b² to find 96 × 84.
25. 25.Use (a − b)² = a² − 2ab + b² to find 74².
26. 26.Use (a − b)² = a² − 2ab + b² to find 38².
27. 27.Find the value of x² − 2xy + y² when x = 9 and y = 8.
28. 28.Use (a + b)(a − b) = a² − b² to find 81 × 79.
29. 29.Use a² − b² = (a + b)(a − b) to find 30² − 6².
30. 30.Use (a + b)² = a² + 2ab + b² to find 23².
31. 31.Find the value of x² + 2xy + y² when x = 7 and y = 3.
32. 32.If a + b = 14 and ab = 40, what is a² + b²?
33. 33.Use (a − b)² = a² − 2ab + b² to find 87².
34. 34.Use (a + b)² = a² + 2ab + b² to find 86².
35. 35.Use a² − b² = (a + b)(a − b) to find 41² − 35².
36. 36.Use (a + b)(a − b) = a² − b² to find 44 × 36.
37. 37.Use (a − b)² = a² − 2ab + b² to find 25².
38. 38.Find the value of x² − y² when x = 12 and y = 4.
39. 39.Use (a − b)² = a² − 2ab + b² to find 41².
40. 40.Use (a − b)² = a² − 2ab + b² to find 46².

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