Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 229 · 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 96².
2. 2.Use (a + b)² = a² + 2ab + b² to find 27².
3. 3.Find the value of x² − 2xy + y² when x = 12 and y = 4.
4. 4.If a − b = 7 and ab = 18, what is a² + b²?
5. 5.Use (a + b)(a − b) = a² − b² to find 34 × 26.
6. 6.Use (a + b)² = a² + 2ab + b² to find 38².
7. 7.Find the value of x² + 2xy + y² when x = 6 and y = 4.
8. 8.Use (a + b)² = a² + 2ab + b² to find 77².
9. 9.Find the value of x² − 2xy + y² when x = 7 and y = 2.
10. 10.If a − b = 4 and ab = 21, what is a² + b²?
11. 11.Use (a + b)(a − b) = a² − b² to find 109 × 91.
12. 12.Use a² − b² = (a + b)(a − b) to find 92² − 59².
13. 13.Use a² − b² = (a + b)(a − b) to find 43² − 5².
14. 14.Use (a + b)(a − b) = a² − b² to find 23 × 17.
15. 15.Use (a − b)² = a² − 2ab + b² to find 24².
16. 16.Use (a + b)² = a² + 2ab + b² to find 48².
17. 17.Use a² − b² = (a + b)(a − b) to find 36² − 2².
18. 18.If a − b = 2 and ab = 3, what is a² + b²?
19. 19.Use (a + b)² = a² + 2ab + b² to find 87².
20. 20.Use (a + b)(a − b) = a² − b² to find 44 × 36.
21. 21.Use (a − b)² = a² − 2ab + b² to find 29².
22. 22.Find the value of x² − y² when x = 4 and y = 2.
23. 23.Use (a + b)² = a² + 2ab + b² to find 35².
24. 24.Find the value of x² + 2xy + y² when x = 3 and y = 1.
25. 25.Use (a + b)(a − b) = a² − b² to find 72 × 68.
26. 26.Use (a + b)(a − b) = a² − b² to find 21 × 19.
27. 27.Use a² − b² = (a + b)(a − b) to find 80² − 62².
28. 28.Use (a − b)² = a² − 2ab + b² to find 31².
29. 29.Use (a − b)² = a² − 2ab + b² to find 16².
30. 30.Use (a + b)(a − b) = a² − b² to find 75 × 65.
31. 31.Use a² − b² = (a + b)(a − b) to find 65² − 30².
32. 32.Use (a + b)(a − b) = a² − b² to find 32 × 28.
33. 33.Use (a + b)² = a² + 2ab + b² to find 22².
34. 34.Use (a + b)(a − b) = a² − b² to find 85 × 75.
35. 35.Find the value of x² − 2xy + y² when x = 4 and y = 2.
36. 36.If a + b = 4 and ab = 3, what is a² + b²?
37. 37.If a + b = 10 and ab = 21, what is a² + b²?
38. 38.Use (a + b)² = a² + 2ab + b² to find 21².
39. 39.Use (a − b)² = a² − 2ab + b² to find 66².
40. 40.If a − b = 1 and ab = 2, what is a² + b²?

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