Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 736 · 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 a² − b² = (a + b)(a − b) to find 70² − 14².
2. 2.If a − b = 5 and ab = 6, what is a² + b²?
3. 3.Use (a + b)(a − b) = a² − b² to find 73 × 67.
4. 4.Find the value of x² − 2xy + y² when x = 15 and y = 14.
5. 5.Use a² − b² = (a + b)(a − b) to find 95² − 22².
6. 6.Find the value of x² + 2xy + y² when x = 4 and y = 1.
7. 7.Use a² − b² = (a + b)(a − b) to find 80² − 21².
8. 8.Find the value of x² + 2xy + y² when x = 13 and y = 4.
9. 9.Use (a + b)² = a² + 2ab + b² to find 27².
10. 10.Use (a − b)² = a² − 2ab + b² to find 26².
11. 11.Use (a − b)² = a² − 2ab + b² to find 46².
12. 12.Use (a + b)² = a² + 2ab + b² to find 92².
13. 13.If a − b = 1 and ab = 2, what is a² + b²?
14. 14.Use (a + b)(a − b) = a² − b² to find 107 × 93.
15. 15.Use (a − b)² = a² − 2ab + b² to find 69².
16. 16.Use a² − b² = (a + b)(a − b) to find 76² − 22².
17. 17.Use a² − b² = (a + b)(a − b) to find 79² − 37².
18. 18.Find the value of x² − 2xy + y² when x = 11 and y = 1.
19. 19.Use (a + b)² = a² + 2ab + b² to find 13².
20. 20.If a + b = 13 and ab = 30, what is a² + b²?
21. 21.Use (a + b)(a − b) = a² − b² to find 48 × 32.
22. 22.Use a² − b² = (a + b)(a − b) to find 30² − 6².
23. 23.Find the value of x² + 2xy + y² when x = 6 and y = 2.
24. 24.If a − b = 11 and ab = 12, what is a² + b²?
25. 25.Use (a + b)(a − b) = a² − b² to find 89 × 71.
26. 26.Use (a − b)² = a² − 2ab + b² to find 18².
27. 27.Find the value of x² − y² when x = 11 and y = 7.
28. 28.Find the value of x² + 2xy + y² when x = 12 and y = 3.
29. 29.Use (a + b)² = a² + 2ab + b² to find 75².
30. 30.Find the value of x² − y² when x = 10 and y = 9.
31. 31.Find the value of x² + 2xy + y² when x = 5 and y = 1.
32. 32.Use (a + b)² = a² + 2ab + b² to find 56².
33. 33.Use (a + b)² = a² + 2ab + b² to find 93².
34. 34.If a + b = 18 and ab = 72, what is a² + b²?
35. 35.Use a² − b² = (a + b)(a − b) to find 61² − 44².
36. 36.Use a² − b² = (a + b)(a − b) to find 31² − 26².
37. 37.Use (a − b)² = a² − 2ab + b² to find 24².
38. 38.Use a² − b² = (a + b)(a − b) to find 85² − 47².
39. 39.Use (a − b)² = a² − 2ab + b² to find 25².
40. 40.Use (a − b)² = a² − 2ab + b² to find 72².

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