Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 58 · 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.Find the value of x² − y² when x = 8 and y = 3.
2. 2.Use (a + b)² = a² + 2ab + b² to find 67².
3. 3.If a + b = 9 and ab = 18, what is a² + b²?
4. 4.Use a² − b² = (a + b)(a − b) to find 45² − 31².
5. 5.Use (a + b)(a − b) = a² − b² to find 21 × 19.
6. 6.Use a² − b² = (a + b)(a − b) to find 32² − 12².
7. 7.Find the value of x² − 2xy + y² when x = 9 and y = 7.
8. 8.Use a² − b² = (a + b)(a − b) to find 72² − 42².
9. 9.If a + b = 7 and ab = 6, what is a² + b²?
10. 10.If a + b = 23 and ab = 132, what is a² + b²?
11. 11.Find the value of x² − 2xy + y² when x = 10 and y = 5.
12. 12.If a + b = 4 and ab = 3, what is a² + b²?
13. 13.Find the value of x² − 2xy + y² when x = 8 and y = 3.
14. 14.Use (a + b)(a − b) = a² − b² to find 84 × 76.
15. 15.If a + b = 7 and ab = 12, what is a² + b²?
16. 16.Find the value of x² − y² when x = 11 and y = 7.
17. 17.Use (a + b)(a − b) = a² − b² to find 81 × 79.
18. 18.Find the value of x² + 2xy + y² when x = 11 and y = 5.
19. 19.Use (a + b)² = a² + 2ab + b² to find 45².
20. 20.Use (a + b)² = a² + 2ab + b² to find 56².
21. 21.Use a² − b² = (a + b)(a − b) to find 47² − 33².
22. 22.Find the value of x² + 2xy + y² when x = 8 and y = 3.
23. 23.Use a² − b² = (a + b)(a − b) to find 29² − 19².
24. 24.If a + b = 9 and ab = 8, what is a² + b²?
25. 25.Find the value of x² + 2xy + y² when x = 15 and y = 13.
26. 26.Use (a + b)(a − b) = a² − b² to find 91 × 89.
27. 27.Use (a − b)² = a² − 2ab + b² to find 93².
28. 28.Find the value of x² − y² when x = 13 and y = 9.
29. 29.If a − b = 11 and ab = 12, what is a² + b²?
30. 30.Use (a + b)(a − b) = a² − b² to find 42 × 38.
31. 31.Use (a − b)² = a² − 2ab + b² to find 63².
32. 32.Use a² − b² = (a + b)(a − b) to find 58² − 35².
33. 33.Find the value of x² + 2xy + y² when x = 15 and y = 3.
34. 34.Use (a − b)² = a² − 2ab + b² to find 85².
35. 35.Use (a − b)² = a² − 2ab + b² to find 27².
36. 36.Use a² − b² = (a + b)(a − b) to find 80² − 2².
37. 37.Find the value of x² − y² when x = 7 and y = 1.
38. 38.Find the value of x² + 2xy + y² when x = 9 and y = 8.
39. 39.Find the value of x² + 2xy + y² when x = 12 and y = 7.
40. 40.Find the value of x² + 2xy + y² when x = 10 and y = 6.

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