Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 483 · 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 = 19 and ab = 88, what is a² + b²?
2. 2.If a − b = 1 and ab = 12, what is a² + b²?
3. 3.If a + b = 15 and ab = 56, what is a² + b²?
4. 4.Use (a + b)² = a² + 2ab + b² to find 68².
5. 5.Use (a − b)² = a² − 2ab + b² to find 39².
6. 6.Find the value of x² − y² when x = 9 and y = 3.
7. 7.Find the value of x² − 2xy + y² when x = 15 and y = 7.
8. 8.Use (a − b)² = a² − 2ab + b² to find 23².
9. 9.Use (a + b)² = a² + 2ab + b² to find 11².
10. 10.Use a² − b² = (a + b)(a − b) to find 61² − 10².
11. 11.Use a² − b² = (a + b)(a − b) to find 63² − 42².
12. 12.Find the value of x² − y² when x = 14 and y = 9.
13. 13.Use (a + b)² = a² + 2ab + b² to find 26².
14. 14.Find the value of x² − y² when x = 12 and y = 11.
15. 15.Use (a − b)² = a² − 2ab + b² to find 63².
16. 16.If a + b = 3 and ab = 2, what is a² + b²?
17. 17.Find the value of x² − 2xy + y² when x = 4 and y = 2.
18. 18.Use (a + b)² = a² + 2ab + b² to find 74².
19. 19.Use (a + b)² = a² + 2ab + b² to find 38².
20. 20.Use (a − b)² = a² − 2ab + b² to find 16².
21. 21.Use (a − b)² = a² − 2ab + b² to find 75².
22. 22.Use a² − b² = (a + b)(a − b) to find 91² − 26².
23. 23.If a − b = 4 and ab = 96, what is a² + b²?
24. 24.Use a² − b² = (a + b)(a − b) to find 94² − 40².
25. 25.Use (a − b)² = a² − 2ab + b² to find 29².
26. 26.If a − b = 1 and ab = 110, what is a² + b²?
27. 27.Use (a − b)² = a² − 2ab + b² to find 58².
28. 28.If a − b = 1 and ab = 132, what is a² + b²?
29. 29.Use a² − b² = (a + b)(a − b) to find 95² − 33².
30. 30.Use a² − b² = (a + b)(a − b) to find 43² − 3².
31. 31.If a + b = 12 and ab = 27, what is a² + b²?
32. 32.Use (a − b)² = a² − 2ab + b² to find 68².
33. 33.If a + b = 4 and ab = 3, what is a² + b²?
34. 34.Use (a + b)(a − b) = a² − b² to find 21 × 19.
35. 35.Use (a + b)(a − b) = a² − b² to find 94 × 86.
36. 36.Use (a + b)(a − b) = a² − b² to find 108 × 92.
37. 37.If a + b = 21 and ab = 110, what is a² + b²?
38. 38.Use a² − b² = (a + b)(a − b) to find 56² − 5².
39. 39.Use (a + b)² = a² + 2ab + b² to find 57².
40. 40.Find the value of x² + 2xy + y² when x = 12 and y = 6.

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