Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 775 · 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 32 × 28.
2. 2.If a − b = 1 and ab = 12, what is a² + b²?
3. 3.Use (a + b)² = a² + 2ab + b² to find 44².
4. 4.Use (a + b)(a − b) = a² − b² to find 74 × 66.
5. 5.Find the value of x² − y² when x = 9 and y = 4.
6. 6.Find the value of x² − 2xy + y² when x = 5 and y = 1.
7. 7.Use (a − b)² = a² − 2ab + b² to find 16².
8. 8.Use (a + b)² = a² + 2ab + b² to find 23².
9. 9.If a + b = 7 and ab = 12, what is a² + b²?
10. 10.Use (a + b)(a − b) = a² − b² to find 92 × 88.
11. 11.Use (a + b)(a − b) = a² − b² to find 85 × 75.
12. 12.If a + b = 10 and ab = 24, what is a² + b²?
13. 13.Use (a + b)(a − b) = a² − b² to find 103 × 97.
14. 14.If a − b = 6 and ab = 40, what is a² + b²?
15. 15.Use (a − b)² = a² − 2ab + b² to find 24².
16. 16.Use (a + b)(a − b) = a² − b² to find 49 × 31.
17. 17.Use a² − b² = (a + b)(a − b) to find 58² − 2².
18. 18.Use a² − b² = (a + b)(a − b) to find 41² − 40².
19. 19.Find the value of x² − y² when x = 12 and y = 5.
20. 20.Use (a − b)² = a² − 2ab + b² to find 93².
21. 21.Use a² − b² = (a + b)(a − b) to find 96² − 64².
22. 22.Find the value of x² + 2xy + y² when x = 15 and y = 8.
23. 23.Use a² − b² = (a + b)(a − b) to find 94² − 79².
24. 24.Find the value of x² − 2xy + y² when x = 3 and y = 2.
25. 25.Find the value of x² + 2xy + y² when x = 5 and y = 3.
26. 26.Use (a + b)(a − b) = a² − b² to find 33 × 27.
27. 27.Find the value of x² − y² when x = 3 and y = 2.
28. 28.Use (a + b)(a − b) = a² − b² to find 51 × 49.
29. 29.Find the value of x² + 2xy + y² when x = 9 and y = 2.
30. 30.Use a² − b² = (a + b)(a − b) to find 90² − 56².
31. 31.Use (a + b)² = a² + 2ab + b² to find 56².
32. 32.Find the value of x² − y² when x = 13 and y = 4.
33. 33.Use (a + b)(a − b) = a² − b² to find 91 × 89.
34. 34.Find the value of x² − 2xy + y² when x = 11 and y = 2.
35. 35.Find the value of x² − 2xy + y² when x = 12 and y = 8.
36. 36.Use (a + b)² = a² + 2ab + b² to find 57².
37. 37.Find the value of x² + 2xy + y² when x = 10 and y = 6.
38. 38.Use (a − b)² = a² − 2ab + b² to find 86².
39. 39.Use (a + b)² = a² + 2ab + b² to find 86².
40. 40.Use a² − b² = (a + b)(a − b) to find 87² − 54².

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