Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 661 · 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 = 6, what is a² + b²?
2. 2.Find the value of x² + 2xy + y² when x = 3 and y = 2.
3. 3.Find the value of x² − y² when x = 5 and y = 1.
4. 4.If a + b = 7 and ab = 12, what is a² + b²?
5. 5.Use (a − b)² = a² − 2ab + b² to find 97².
6. 6.Find the value of x² − 2xy + y² when x = 3 and y = 1.
7. 7.Find the value of x² − 2xy + y² when x = 6 and y = 1.
8. 8.Use (a − b)² = a² − 2ab + b² to find 46².
9. 9.Use (a + b)² = a² + 2ab + b² to find 55².
10. 10.Use (a + b)² = a² + 2ab + b² to find 52².
11. 11.Use (a + b)² = a² + 2ab + b² to find 57².
12. 12.Use (a + b)² = a² + 2ab + b² to find 21².
13. 13.Use (a + b)(a − b) = a² − b² to find 34 × 26.
14. 14.Find the value of x² + 2xy + y² when x = 5 and y = 3.
15. 15.Find the value of x² + 2xy + y² when x = 10 and y = 4.
16. 16.If a − b = 7 and ab = 8, what is a² + b²?
17. 17.Use (a − b)² = a² − 2ab + b² to find 23².
18. 18.Use a² − b² = (a + b)(a − b) to find 27² − 17².
19. 19.If a + b = 18 and ab = 72, what is a² + b²?
20. 20.If a − b = 4 and ab = 12, what is a² + b²?
21. 21.Use (a + b)² = a² + 2ab + b² to find 12².
22. 22.Use (a + b)² = a² + 2ab + b² to find 93².
23. 23.Use (a − b)² = a² − 2ab + b² to find 17².
24. 24.Use (a − b)² = a² − 2ab + b² to find 39².
25. 25.If a − b = 1 and ab = 2, what is a² + b²?
26. 26.Find the value of x² + 2xy + y² when x = 13 and y = 2.
27. 27.Find the value of x² − y² when x = 8 and y = 2.
28. 28.Find the value of x² − y² when x = 5 and y = 4.
29. 29.Use a² − b² = (a + b)(a − b) to find 57² − 14².
30. 30.Use a² − b² = (a + b)(a − b) to find 96² − 4².
31. 31.Use (a − b)² = a² − 2ab + b² to find 75².
32. 32.Use a² − b² = (a + b)(a − b) to find 58² − 34².
33. 33.Use (a − b)² = a² − 2ab + b² to find 58².
34. 34.Use (a + b)² = a² + 2ab + b² to find 62².
35. 35.Use a² − b² = (a + b)(a − b) to find 60² − 57².
36. 36.Use (a + b)(a − b) = a² − b² to find 62 × 58.
37. 37.Use (a − b)² = a² − 2ab + b² to find 96².
38. 38.Use (a + b)(a − b) = a² − b² to find 35 × 25.
39. 39.Use (a + b)(a − b) = a² − b² to find 37 × 23.
40. 40.Use (a + b)(a − b) = a² − b² to find 23 × 17.

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