Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 369 · 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)(a − b) = a² − b² to find 31 × 29.
2. 2.Find the value of x² + 2xy + y² when x = 13 and y = 8.
3. 3.Find the value of x² − 2xy + y² when x = 11 and y = 4.
4. 4.Find the value of x² + 2xy + y² when x = 3 and y = 2.
5. 5.Find the value of x² + 2xy + y² when x = 4 and y = 3.
6. 6.If a − b = 4 and ab = 5, what is a² + b²?
7. 7.If a − b = 3 and ab = 88, what is a² + b²?
8. 8.If a + b = 18 and ab = 77, what is a² + b²?
9. 9.Use a² − b² = (a + b)(a − b) to find 66² − 8².
10. 10.Use (a + b)(a − b) = a² − b² to find 102 × 98.
11. 11.Use (a + b)² = a² + 2ab + b² to find 81².
12. 12.Use a² − b² = (a + b)(a − b) to find 48² − 6².
13. 13.Use (a + b)(a − b) = a² − b² to find 92 × 88.
14. 14.Use (a + b)² = a² + 2ab + b² to find 63².
15. 15.Use a² − b² = (a + b)(a − b) to find 20² − 8².
16. 16.Use a² − b² = (a + b)(a − b) to find 76² − 34².
17. 17.Use a² − b² = (a + b)(a − b) to find 89² − 77².
18. 18.Use (a + b)² = a² + 2ab + b² to find 37².
19. 19.Use (a − b)² = a² − 2ab + b² to find 26².
20. 20.If a + b = 3 and ab = 2, what is a² + b²?
21. 21.Use (a + b)² = a² + 2ab + b² to find 24².
22. 22.Use (a + b)(a − b) = a² − b² to find 68 × 52.
23. 23.If a + b = 5 and ab = 4, what is a² + b²?
24. 24.Use (a + b)² = a² + 2ab + b² to find 28².
25. 25.Find the value of x² + 2xy + y² when x = 14 and y = 7.
26. 26.Find the value of x² − y² when x = 7 and y = 1.
27. 27.Use (a + b)² = a² + 2ab + b² to find 38².
28. 28.If a + b = 17 and ab = 66, what is a² + b²?
29. 29.Find the value of x² − 2xy + y² when x = 9 and y = 8.
30. 30.Use (a + b)² = a² + 2ab + b² to find 52².
31. 31.If a + b = 7 and ab = 10, what is a² + b²?
32. 32.Use (a + b)(a − b) = a² − b² to find 64 × 56.
33. 33.Use (a − b)² = a² − 2ab + b² to find 22².
34. 34.Find the value of x² − y² when x = 6 and y = 1.
35. 35.Use (a + b)² = a² + 2ab + b² to find 41².
36. 36.If a − b = 7 and ab = 60, what is a² + b²?
37. 37.Use (a − b)² = a² − 2ab + b² to find 15².
38. 38.Use (a + b)(a − b) = a² − b² to find 55 × 45.
39. 39.Use (a + b)² = a² + 2ab + b² to find 97².
40. 40.Use (a − b)² = a² − 2ab + b² to find 11².

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