Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 963 · 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 105 × 95.
2. 2.Use (a − b)² = a² − 2ab + b² to find 79².
3. 3.Find the value of x² − 2xy + y² when x = 7 and y = 6.
4. 4.Use (a + b)(a − b) = a² − b² to find 53 × 47.
5. 5.Use (a − b)² = a² − 2ab + b² to find 92².
6. 6.Use (a + b)(a − b) = a² − b² to find 86 × 74.
7. 7.If a − b = 2 and ab = 15, what is a² + b²?
8. 8.Use (a − b)² = a² − 2ab + b² to find 89².
9. 9.Find the value of x² − 2xy + y² when x = 14 and y = 6.
10. 10.If a + b = 19 and ab = 90, what is a² + b²?
11. 11.Use (a + b)(a − b) = a² − b² to find 22 × 18.
12. 12.Use a² − b² = (a + b)(a − b) to find 87² − 2².
13. 13.Use (a − b)² = a² − 2ab + b² to find 31².
14. 14.Find the value of x² + 2xy + y² when x = 12 and y = 10.
15. 15.Use a² − b² = (a + b)(a − b) to find 55² − 22².
16. 16.Use (a − b)² = a² − 2ab + b² to find 87².
17. 17.Find the value of x² + 2xy + y² when x = 9 and y = 8.
18. 18.If a − b = 5 and ab = 24, what is a² + b²?
19. 19.Find the value of x² + 2xy + y² when x = 10 and y = 8.
20. 20.Use a² − b² = (a + b)(a − b) to find 64² − 4².
21. 21.Use (a − b)² = a² − 2ab + b² to find 95².
22. 22.Use (a − b)² = a² − 2ab + b² to find 21².
23. 23.Use (a − b)² = a² − 2ab + b² to find 27².
24. 24.Use a² − b² = (a + b)(a − b) to find 66² − 61².
25. 25.Use (a + b)(a − b) = a² − b² to find 21 × 19.
26. 26.If a − b = 1 and ab = 12, what is a² + b²?
27. 27.Use (a + b)² = a² + 2ab + b² to find 66².
28. 28.Use (a + b)² = a² + 2ab + b² to find 37².
29. 29.If a + b = 16 and ab = 55, what is a² + b²?
30. 30.Find the value of x² − y² when x = 12 and y = 6.
31. 31.Use a² − b² = (a + b)(a − b) to find 49² − 39².
32. 32.If a + b = 7 and ab = 6, what is a² + b²?
33. 33.Use (a − b)² = a² − 2ab + b² to find 41².
34. 34.If a + b = 10 and ab = 21, what is a² + b²?
35. 35.Use (a + b)(a − b) = a² − b² to find 91 × 89.
36. 36.Find the value of x² − y² when x = 6 and y = 2.
37. 37.Use a² − b² = (a + b)(a − b) to find 21² − 14².
38. 38.Use (a + b)(a − b) = a² − b² to find 41 × 39.
39. 39.Use a² − b² = (a + b)(a − b) to find 63² − 31².
40. 40.Use (a + b)(a − b) = a² − b² to find 35 × 25.

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