Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 72 · 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 a² − b² = (a + b)(a − b) to find 30² − 13².
2. 2.Use (a + b)² = a² + 2ab + b² to find 36².
3. 3.Use a² − b² = (a + b)(a − b) to find 84² − 7².
4. 4.Use a² − b² = (a + b)(a − b) to find 77² − 65².
5. 5.Use a² − b² = (a + b)(a − b) to find 73² − 42².
6. 6.Use (a + b)² = a² + 2ab + b² to find 59².
7. 7.Use (a − b)² = a² − 2ab + b² to find 18².
8. 8.Use (a + b)² = a² + 2ab + b² to find 96².
9. 9.Use (a + b)(a − b) = a² − b² to find 44 × 36.
10. 10.Find the value of x² + 2xy + y² when x = 15 and y = 7.
11. 11.Use (a − b)² = a² − 2ab + b² to find 37².
12. 12.Use a² − b² = (a + b)(a − b) to find 86² − 73².
13. 13.Use (a + b)(a − b) = a² − b² to find 45 × 35.
14. 14.Use (a + b)² = a² + 2ab + b² to find 12².
15. 15.Use (a + b)² = a² + 2ab + b² to find 101².
16. 16.Use a² − b² = (a + b)(a − b) to find 25² − 17².
17. 17.Use (a + b)(a − b) = a² − b² to find 88 × 72.
18. 18.Use (a + b)(a − b) = a² − b² to find 94 × 86.
19. 19.Use (a − b)² = a² − 2ab + b² to find 51².
20. 20.If a + b = 8 and ab = 12, what is a² + b²?
21. 21.Use a² − b² = (a + b)(a − b) to find 94² − 37².
22. 22.Use (a + b)(a − b) = a² − b² to find 97 × 83.
23. 23.Use (a − b)² = a² − 2ab + b² to find 96².
24. 24.Use (a + b)² = a² + 2ab + b² to find 63².
25. 25.Use (a + b)(a − b) = a² − b² to find 33 × 27.
26. 26.Use (a + b)(a − b) = a² − b² to find 41 × 39.
27. 27.Use a² − b² = (a + b)(a − b) to find 73² − 14².
28. 28.Use (a + b)(a − b) = a² − b² to find 91 × 89.
29. 29.Use a² − b² = (a + b)(a − b) to find 36² − 24².
30. 30.Find the value of x² − y² when x = 13 and y = 10.
31. 31.Use (a + b)² = a² + 2ab + b² to find 78².
32. 32.Use a² − b² = (a + b)(a − b) to find 58² − 52².
33. 33.Use (a + b)² = a² + 2ab + b² to find 104².
34. 34.Find the value of x² + 2xy + y² when x = 7 and y = 1.
35. 35.Use a² − b² = (a + b)(a − b) to find 81² − 31².
36. 36.Use (a + b)(a − b) = a² − b² to find 21 × 19.
37. 37.Use (a + b)² = a² + 2ab + b² to find 21².
38. 38.Find the value of x² − 2xy + y² when x = 14 and y = 1.
39. 39.If a − b = 6 and ab = 16, what is a² + b²?
40. 40.If a + b = 8 and ab = 7, what is a² + b²?

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