Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 518 · 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 87².
2. 2.Find the value of x² − y² when x = 12 and y = 3.
3. 3.Use (a + b)(a − b) = a² − b² to find 84 × 76.
4. 4.Use (a + b)(a − b) = a² − b² to find 67 × 53.
5. 5.Use (a + b)(a − b) = a² − b² to find 108 × 92.
6. 6.Use (a + b)² = a² + 2ab + b² to find 46².
7. 7.Use (a − b)² = a² − 2ab + b² to find 27².
8. 8.Use (a + b)² = a² + 2ab + b² to find 73².
9. 9.Use (a + b)(a − b) = a² − b² to find 39 × 21.
10. 10.If a + b = 13 and ab = 30, what is a² + b²?
11. 11.If a + b = 12 and ab = 32, what is a² + b²?
12. 12.If a − b = 1 and ab = 12, what is a² + b²?
13. 13.Use (a + b)² = a² + 2ab + b² to find 91².
14. 14.Find the value of x² − 2xy + y² when x = 9 and y = 3.
15. 15.Use (a + b)(a − b) = a² − b² to find 32 × 28.
16. 16.Use a² − b² = (a + b)(a − b) to find 45² − 32².
17. 17.Use a² − b² = (a + b)(a − b) to find 64² − 13².
18. 18.Use (a − b)² = a² − 2ab + b² to find 65².
19. 19.Use a² − b² = (a + b)(a − b) to find 92² − 56².
20. 20.Use (a + b)² = a² + 2ab + b² to find 39².
21. 21.Use a² − b² = (a + b)(a − b) to find 52² − 14².
22. 22.Use (a + b)² = a² + 2ab + b² to find 12².
23. 23.Use (a − b)² = a² − 2ab + b² to find 62².
24. 24.Use a² − b² = (a + b)(a − b) to find 75² − 25².
25. 25.Use (a − b)² = a² − 2ab + b² to find 88².
26. 26.Use (a + b)² = a² + 2ab + b² to find 66².
27. 27.Use a² − b² = (a + b)(a − b) to find 41² − 33².
28. 28.Find the value of x² − 2xy + y² when x = 15 and y = 8.
29. 29.Use (a + b)² = a² + 2ab + b² to find 26².
30. 30.Find the value of x² − 2xy + y² when x = 9 and y = 5.
31. 31.Use (a + b)² = a² + 2ab + b² to find 81².
32. 32.Use (a + b)² = a² + 2ab + b² to find 57².
33. 33.Use (a + b)² = a² + 2ab + b² to find 25².
34. 34.Find the value of x² + 2xy + y² when x = 8 and y = 2.
35. 35.Use (a + b)² = a² + 2ab + b² to find 23².
36. 36.Use a² − b² = (a + b)(a − b) to find 92² − 90².
37. 37.Use (a + b)(a − b) = a² − b² to find 47 × 33.
38. 38.Use a² − b² = (a + b)(a − b) to find 40² − 24².
39. 39.Use (a + b)² = a² + 2ab + b² to find 55².
40. 40.If a − b = 6 and ab = 40, what is a² + b²?

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