Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 539 · 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 26².
2. 2.Use (a + b)² = a² + 2ab + b² to find 77².
3. 3.Use (a + b)² = a² + 2ab + b² to find 79².
4. 4.Use (a + b)² = a² + 2ab + b² to find 72².
5. 5.Use (a + b)² = a² + 2ab + b² to find 61².
6. 6.Use (a − b)² = a² − 2ab + b² to find 15².
7. 7.Find the value of x² − 2xy + y² when x = 12 and y = 4.
8. 8.Find the value of x² − 2xy + y² when x = 5 and y = 4.
9. 9.Find the value of x² − 2xy + y² when x = 6 and y = 2.
10. 10.Use (a + b)² = a² + 2ab + b² to find 64².
11. 11.Use (a − b)² = a² − 2ab + b² to find 99².
12. 12.Use (a + b)² = a² + 2ab + b² to find 88².
13. 13.Find the value of x² − y² when x = 14 and y = 9.
14. 14.Find the value of x² − 2xy + y² when x = 15 and y = 12.
15. 15.Use (a + b)(a − b) = a² − b² to find 93 × 87.
16. 16.Use (a − b)² = a² − 2ab + b² to find 23².
17. 17.Use (a + b)² = a² + 2ab + b² to find 63².
18. 18.If a − b = 1 and ab = 2, what is a² + b²?
19. 19.Use (a + b)(a − b) = a² − b² to find 43 × 37.
20. 20.Use (a − b)² = a² − 2ab + b² to find 43².
21. 21.Use (a + b)(a − b) = a² − b² to find 49 × 31.
22. 22.Find the value of x² − 2xy + y² when x = 14 and y = 3.
23. 23.Use a² − b² = (a + b)(a − b) to find 30² − 12².
24. 24.Use (a − b)² = a² − 2ab + b² to find 67².
25. 25.Find the value of x² + 2xy + y² when x = 12 and y = 9.
26. 26.If a + b = 7 and ab = 12, what is a² + b²?
27. 27.Use (a + b)(a − b) = a² − b² to find 78 × 62.
28. 28.Use a² − b² = (a + b)(a − b) to find 86² − 16².
29. 29.Use (a − b)² = a² − 2ab + b² to find 38².
30. 30.Find the value of x² − y² when x = 9 and y = 4.
31. 31.Use (a + b)(a − b) = a² − b² to find 105 × 95.
32. 32.Use a² − b² = (a + b)(a − b) to find 48² − 47².
33. 33.Use (a − b)² = a² − 2ab + b² to find 58².
34. 34.Use a² − b² = (a + b)(a − b) to find 98² − 15².
35. 35.Use (a + b)² = a² + 2ab + b² to find 32².
36. 36.Find the value of x² + 2xy + y² when x = 5 and y = 4.
37. 37.Use (a − b)² = a² − 2ab + b² to find 55².
38. 38.Use a² − b² = (a + b)(a − b) to find 31² − 27².
39. 39.Find the value of x² − y² when x = 4 and y = 1.
40. 40.Find the value of x² − 2xy + y² when x = 13 and y = 12.

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