Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 807 · 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.If a − b = 2 and ab = 8, what is a² + b²?
2. 2.Use (a + b)² = a² + 2ab + b² to find 13².
3. 3.Find the value of x² + 2xy + y² when x = 4 and y = 3.
4. 4.If a + b = 14 and ab = 33, what is a² + b²?
5. 5.Use (a + b)² = a² + 2ab + b² to find 56².
6. 6.Use (a + b)(a − b) = a² − b² to find 69 × 51.
7. 7.Use a² − b² = (a + b)(a − b) to find 28² − 3².
8. 8.If a + b = 8 and ab = 7, what is a² + b²?
9. 9.Use (a − b)² = a² − 2ab + b² to find 45².
10. 10.Use (a − b)² = a² − 2ab + b² to find 98².
11. 11.Find the value of x² − y² when x = 15 and y = 1.
12. 12.Use (a + b)² = a² + 2ab + b² to find 109².
13. 13.Use (a + b)² = a² + 2ab + b² to find 106².
14. 14.If a − b = 5 and ab = 36, what is a² + b²?
15. 15.Use (a + b)² = a² + 2ab + b² to find 11².
16. 16.Use a² − b² = (a + b)(a − b) to find 49² − 48².
17. 17.Use (a + b)² = a² + 2ab + b² to find 47².
18. 18.Use a² − b² = (a + b)(a − b) to find 20² − 4².
19. 19.Find the value of x² − 2xy + y² when x = 13 and y = 9.
20. 20.Use (a + b)(a − b) = a² − b² to find 72 × 68.
21. 21.If a − b = 2 and ab = 99, what is a² + b²?
22. 22.If a − b = 8 and ab = 9, what is a² + b²?
23. 23.Use (a − b)² = a² − 2ab + b² to find 17².
24. 24.If a − b = 2 and ab = 15, what is a² + b²?
25. 25.If a + b = 7 and ab = 12, what is a² + b²?
26. 26.If a + b = 11 and ab = 28, what is a² + b²?
27. 27.Use a² − b² = (a + b)(a − b) to find 37² − 6².
28. 28.If a + b = 14 and ab = 48, what is a² + b²?
29. 29.Use (a − b)² = a² − 2ab + b² to find 79².
30. 30.Find the value of x² + 2xy + y² when x = 5 and y = 2.
31. 31.Use a² − b² = (a + b)(a − b) to find 57² − 33².
32. 32.Use (a + b)² = a² + 2ab + b² to find 58².
33. 33.Use (a + b)(a − b) = a² − b² to find 92 × 88.
34. 34.Use (a − b)² = a² − 2ab + b² to find 58².
35. 35.Use (a − b)² = a² − 2ab + b² to find 71².
36. 36.Use a² − b² = (a + b)(a − b) to find 59² − 27².
37. 37.If a + b = 19 and ab = 90, what is a² + b²?
38. 38.Find the value of x² + 2xy + y² when x = 8 and y = 5.
39. 39.If a + b = 4 and ab = 3, what is a² + b²?
40. 40.Use (a + b)(a − b) = a² − b² to find 47 × 33.

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