Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 691 · 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 24².
2. 2.Use (a + b)² = a² + 2ab + b² to find 58².
3. 3.Use a² − b² = (a + b)(a − b) to find 68² − 6².
4. 4.Use (a + b)(a − b) = a² − b² to find 65 × 55.
5. 5.Use a² − b² = (a + b)(a − b) to find 68² − 51².
6. 6.If a + b = 7 and ab = 12, what is a² + b²?
7. 7.Use (a − b)² = a² − 2ab + b² to find 95².
8. 8.Use (a − b)² = a² − 2ab + b² to find 25².
9. 9.If a − b = 1 and ab = 2, what is a² + b²?
10. 10.If a − b = 5 and ab = 24, what is a² + b²?
11. 11.Use (a + b)² = a² + 2ab + b² to find 25².
12. 12.Use (a − b)² = a² − 2ab + b² to find 84².
13. 13.Use (a + b)² = a² + 2ab + b² to find 23².
14. 14.Use (a + b)² = a² + 2ab + b² to find 103².
15. 15.If a − b = 2 and ab = 3, what is a² + b²?
16. 16.Use a² − b² = (a + b)(a − b) to find 53² − 17².
17. 17.If a + b = 7 and ab = 10, what is a² + b²?
18. 18.If a + b = 3 and ab = 2, what is a² + b²?
19. 19.Use (a − b)² = a² − 2ab + b² to find 49².
20. 20.Use (a − b)² = a² − 2ab + b² to find 22².
21. 21.Find the value of x² + 2xy + y² when x = 10 and y = 2.
22. 22.Find the value of x² − y² when x = 3 and y = 2.
23. 23.If a − b = 6 and ab = 40, what is a² + b²?
24. 24.Use (a + b)² = a² + 2ab + b² to find 102².
25. 25.If a + b = 8 and ab = 7, 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 78 × 62.
28. 28.Use (a + b)(a − b) = a² − b² to find 63 × 57.
29. 29.Use (a − b)² = a² − 2ab + b² to find 37².
30. 30.Use (a + b)(a − b) = a² − b² to find 95 × 85.
31. 31.If a − b = 10 and ab = 24, what is a² + b²?
32. 32.Use (a − b)² = a² − 2ab + b² to find 67².
33. 33.Use (a + b)² = a² + 2ab + b² to find 79².
34. 34.Use (a + b)(a − b) = a² − b² to find 82 × 78.
35. 35.Use a² − b² = (a + b)(a − b) to find 96² − 59².
36. 36.Use (a − b)² = a² − 2ab + b² to find 77².
37. 37.Use a² − b² = (a + b)(a − b) to find 92² − 12².
38. 38.Use (a + b)² = a² + 2ab + b² to find 12².
39. 39.Use (a + b)(a − b) = a² − b² to find 69 × 51.
40. 40.Use (a − b)² = a² − 2ab + b² to find 36².

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