Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 897 · 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 49².
2. 2.Find the value of x² − 2xy + y² when x = 4 and y = 3.
3. 3.Find the value of x² − y² when x = 12 and y = 6.
4. 4.Use a² − b² = (a + b)(a − b) to find 96² − 29².
5. 5.Use a² − b² = (a + b)(a − b) to find 91² − 57².
6. 6.Use (a − b)² = a² − 2ab + b² to find 49².
7. 7.Use (a + b)(a − b) = a² − b² to find 51 × 49.
8. 8.If a − b = 9 and ab = 10, what is a² + b²?
9. 9.Find the value of x² − y² when x = 5 and y = 1.
10. 10.Find the value of x² + 2xy + y² when x = 6 and y = 4.
11. 11.Use (a + b)(a − b) = a² − b² to find 42 × 38.
12. 12.Use a² − b² = (a + b)(a − b) to find 88² − 24².
13. 13.Use (a + b)(a − b) = a² − b² to find 34 × 26.
14. 14.Use (a − b)² = a² − 2ab + b² to find 21².
15. 15.Use (a − b)² = a² − 2ab + b² to find 42².
16. 16.If a + b = 6 and ab = 5, what is a² + b²?
17. 17.Find the value of x² + 2xy + y² when x = 6 and y = 5.
18. 18.Use (a + b)² = a² + 2ab + b² to find 34².
19. 19.Use (a + b)² = a² + 2ab + b² to find 21².
20. 20.Find the value of x² − 2xy + y² when x = 6 and y = 5.
21. 21.Find the value of x² + 2xy + y² when x = 8 and y = 4.
22. 22.Use (a + b)(a − b) = a² − b² to find 82 × 78.
23. 23.Use (a − b)² = a² − 2ab + b² to find 83².
24. 24.Use (a + b)(a − b) = a² − b² to find 22 × 18.
25. 25.Find the value of x² − y² when x = 14 and y = 2.
26. 26.Find the value of x² + 2xy + y² when x = 4 and y = 3.
27. 27.Use a² − b² = (a + b)(a − b) to find 70² − 47².
28. 28.Use (a + b)² = a² + 2ab + b² to find 25².
29. 29.If a + b = 7 and ab = 12, what is a² + b²?
30. 30.If a − b = 5 and ab = 84, what is a² + b²?
31. 31.Use (a − b)² = a² − 2ab + b² to find 22².
32. 32.Use (a + b)² = a² + 2ab + b² to find 31².
33. 33.Find the value of x² − 2xy + y² when x = 13 and y = 12.
34. 34.If a − b = 2 and ab = 3, what is a² + b²?
35. 35.Use (a + b)² = a² + 2ab + b² to find 75².
36. 36.Find the value of x² − y² when x = 13 and y = 3.
37. 37.Use (a − b)² = a² − 2ab + b² to find 33².
38. 38.Use a² − b² = (a + b)(a − b) to find 46² − 21².
39. 39.Find the value of x² − y² when x = 7 and y = 4.
40. 40.Use (a + b)(a − b) = a² − b² to find 87 × 73.

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