Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 197 · 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)(a − b) = a² − b² to find 26 × 14.
2. 2.Use (a + b)² = a² + 2ab + b² to find 102².
3. 3.Use (a + b)(a − b) = a² − b² to find 21 × 19.
4. 4.Use (a − b)² = a² − 2ab + b² to find 19².
5. 5.Use (a + b)(a − b) = a² − b² to find 65 × 55.
6. 6.Find the value of x² − 2xy + y² when x = 12 and y = 7.
7. 7.Use (a − b)² = a² − 2ab + b² to find 11².
8. 8.Use a² − b² = (a + b)(a − b) to find 58² − 44².
9. 9.If a + b = 12 and ab = 11, what is a² + b²?
10. 10.Find the value of x² + 2xy + y² when x = 5 and y = 2.
11. 11.If a + b = 5 and ab = 6, what is a² + b²?
12. 12.Use (a − b)² = a² − 2ab + b² to find 71².
13. 13.Use a² − b² = (a + b)(a − b) to find 35² − 10².
14. 14.Use a² − b² = (a + b)(a − b) to find 40² − 4².
15. 15.Use (a − b)² = a² − 2ab + b² to find 58².
16. 16.Use a² − b² = (a + b)(a − b) to find 43² − 26².
17. 17.Use (a + b)(a − b) = a² − b² to find 64 × 56.
18. 18.Use (a + b)² = a² + 2ab + b² to find 107².
19. 19.Use a² − b² = (a + b)(a − b) to find 79² − 11².
20. 20.Use (a + b)² = a² + 2ab + b² to find 103².
21. 21.Find the value of x² − 2xy + y² when x = 4 and y = 3.
22. 22.Use (a + b)(a − b) = a² − b² to find 22 × 18.
23. 23.Use (a − b)² = a² − 2ab + b² to find 26².
24. 24.Use a² − b² = (a + b)(a − b) to find 36² − 31².
25. 25.Use (a + b)(a − b) = a² − b² to find 75 × 65.
26. 26.Use a² − b² = (a + b)(a − b) to find 69² − 49².
27. 27.Find the value of x² + 2xy + y² when x = 8 and y = 1.
28. 28.Find the value of x² + 2xy + y² when x = 5 and y = 3.
29. 29.Find the value of x² − 2xy + y² when x = 7 and y = 3.
30. 30.Use a² − b² = (a + b)(a − b) to find 41² − 4².
31. 31.Use (a − b)² = a² − 2ab + b² to find 39².
32. 32.Use (a − b)² = a² − 2ab + b² to find 23².
33. 33.Use a² − b² = (a + b)(a − b) to find 48² − 17².
34. 34.Find the value of x² − y² when x = 10 and y = 7.
35. 35.Use a² − b² = (a + b)(a − b) to find 74² − 57².
36. 36.Use (a + b)(a − b) = a² − b² to find 59 × 41.
37. 37.Use (a − b)² = a² − 2ab + b² to find 94².
38. 38.Use (a − b)² = a² − 2ab + b² to find 96².
39. 39.Use (a + b)(a − b) = a² − b² to find 25 × 15.
40. 40.If a + b = 4 and ab = 3, what is a² + b²?

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