Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 634 · 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.If a − b = 1 and ab = 12, what is a² + b²?
2. 2.Use (a − b)² = a² − 2ab + b² to find 21².
3. 3.Find the value of x² − y² when x = 14 and y = 8.
4. 4.Use (a − b)² = a² − 2ab + b² to find 44².
5. 5.Find the value of x² − y² when x = 15 and y = 2.
6. 6.Use (a + b)(a − b) = a² − b² to find 21 × 19.
7. 7.Find the value of x² − 2xy + y² when x = 15 and y = 11.
8. 8.Use (a − b)² = a² − 2ab + b² to find 89².
9. 9.Find the value of x² − y² when x = 6 and y = 5.
10. 10.Use (a + b)(a − b) = a² − b² to find 105 × 95.
11. 11.Use (a + b)² = a² + 2ab + b² to find 47².
12. 12.Use (a + b)(a − b) = a² − b² to find 29 × 11.
13. 13.Use (a + b)(a − b) = a² − b² to find 56 × 44.
14. 14.If a + b = 3 and ab = 2, what is a² + b²?
15. 15.Use (a + b)² = a² + 2ab + b² to find 87².
16. 16.If a − b = 7 and ab = 8, what is a² + b²?
17. 17.Use (a + b)(a − b) = a² − b² to find 77 × 63.
18. 18.Find the value of x² − y² when x = 15 and y = 4.
19. 19.Use (a + b)(a − b) = a² − b² to find 78 × 62.
20. 20.If a + b = 6 and ab = 5, what is a² + b²?
21. 21.Use (a − b)² = a² − 2ab + b² to find 65².
22. 22.Use a² − b² = (a + b)(a − b) to find 28² − 4².
23. 23.Use a² − b² = (a + b)(a − b) to find 66² − 13².
24. 24.Use a² − b² = (a + b)(a − b) to find 32² − 27².
25. 25.If a + b = 10 and ab = 24, what is a² + b²?
26. 26.Find the value of x² − 2xy + y² when x = 7 and y = 6.
27. 27.Use (a + b)(a − b) = a² − b² to find 81 × 79.
28. 28.Find the value of x² + 2xy + y² when x = 10 and y = 8.
29. 29.Use a² − b² = (a + b)(a − b) to find 30² − 21².
30. 30.Use a² − b² = (a + b)(a − b) to find 34² − 5².
31. 31.Find the value of x² − y² when x = 14 and y = 1.
32. 32.Use (a + b)² = a² + 2ab + b² to find 44².
33. 33.Use (a + b)² = a² + 2ab + b² to find 49².
34. 34.Use a² − b² = (a + b)(a − b) to find 80² − 7².
35. 35.Use a² − b² = (a + b)(a − b) to find 34² − 16².
36. 36.Use (a + b)² = a² + 2ab + b² to find 86².
37. 37.Use (a + b)(a − b) = a² − b² to find 108 × 92.
38. 38.Use a² − b² = (a + b)(a − b) to find 62² − 19².
39. 39.If a − b = 1 and ab = 2, what is a² + b²?
40. 40.Use (a − b)² = a² − 2ab + b² to find 41².

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