Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 476 · 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 = 11 and ab = 30, what is a² + b²?
2. 2.Find the value of x² − 2xy + y² when x = 15 and y = 8.
3. 3.Use (a + b)(a − b) = a² − b² to find 91 × 89.
4. 4.Find the value of x² − 2xy + y² when x = 10 and y = 1.
5. 5.Use (a − b)² = a² − 2ab + b² to find 95².
6. 6.Use (a − b)² = a² − 2ab + b² to find 89².
7. 7.Use (a + b)² = a² + 2ab + b² to find 39².
8. 8.Use a² − b² = (a + b)(a − b) to find 20² − 4².
9. 9.Use (a + b)² = a² + 2ab + b² to find 85².
10. 10.Use (a + b)(a − b) = a² − b² to find 27 × 13.
11. 11.Find the value of x² − 2xy + y² when x = 7 and y = 5.
12. 12.Use a² − b² = (a + b)(a − b) to find 60² − 59².
13. 13.Use (a − b)² = a² − 2ab + b² to find 94².
14. 14.If a − b = 1 and ab = 42, what is a² + b²?
15. 15.Use (a + b)(a − b) = a² − b² to find 54 × 46.
16. 16.Use a² − b² = (a + b)(a − b) to find 87² − 12².
17. 17.Use (a − b)² = a² − 2ab + b² to find 67².
18. 18.If a − b = 1 and ab = 90, what is a² + b²?
19. 19.Use (a + b)(a − b) = a² − b² to find 82 × 78.
20. 20.Use (a + b)² = a² + 2ab + b² to find 32².
21. 21.Use (a + b)(a − b) = a² − b² to find 72 × 68.
22. 22.If a + b = 19 and ab = 90, what is a² + b²?
23. 23.If a − b = 1 and ab = 20, what is a² + b²?
24. 24.Use (a − b)² = a² − 2ab + b² to find 96².
25. 25.Use (a + b)² = a² + 2ab + b² to find 24².
26. 26.Use (a + b)(a − b) = a² − b² to find 26 × 14.
27. 27.Find the value of x² − 2xy + y² when x = 4 and y = 1.
28. 28.Use (a + b)² = a² + 2ab + b² to find 72².
29. 29.Use a² − b² = (a + b)(a − b) to find 99² − 82².
30. 30.Use (a + b)(a − b) = a² − b² to find 79 × 61.
31. 31.Use (a + b)² = a² + 2ab + b² to find 93².
32. 32.Use (a + b)(a − b) = a² − b² to find 53 × 47.
33. 33.Use (a + b)(a − b) = a² − b² to find 74 × 66.
34. 34.Find the value of x² − 2xy + y² when x = 6 and y = 4.
35. 35.Use (a + b)(a − b) = a² − b² to find 67 × 53.
36. 36.If a − b = 3 and ab = 54, what is a² + b²?
37. 37.Use a² − b² = (a + b)(a − b) to find 48² − 24².
38. 38.Use a² − b² = (a + b)(a − b) to find 56² − 32².
39. 39.Use a² − b² = (a + b)(a − b) to find 45² − 6².
40. 40.Use a² − b² = (a + b)(a − b) to find 81² − 76².

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