Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 25 · 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.Find the value of x² − 2xy + y² when x = 4 and y = 1.
2. 2.Use (a + b)(a − b) = a² − b² to find 84 × 76.
3. 3.If a + b = 13 and ab = 40, what is a² + b²?
4. 4.Use (a − b)² = a² − 2ab + b² to find 94².
5. 5.Use (a + b)(a − b) = a² − b² to find 21 × 19.
6. 6.Use (a + b)(a − b) = a² − b² to find 28 × 12.
7. 7.Use (a + b)(a − b) = a² − b² to find 63 × 57.
8. 8.Use (a − b)² = a² − 2ab + b² to find 84².
9. 9.Use (a + b)² = a² + 2ab + b² to find 73².
10. 10.If a − b = 2 and ab = 15, what is a² + b²?
11. 11.Find the value of x² − 2xy + y² when x = 6 and y = 3.
12. 12.Use (a + b)(a − b) = a² − b² to find 38 × 22.
13. 13.If a + b = 9 and ab = 20, what is a² + b²?
14. 14.Use (a + b)² = a² + 2ab + b² to find 39².
15. 15.If a − b = 6 and ab = 27, what is a² + b²?
16. 16.Use (a − b)² = a² − 2ab + b² to find 82².
17. 17.Use a² − b² = (a + b)(a − b) to find 50² − 7².
18. 18.Use a² − b² = (a + b)(a − b) to find 39² − 14².
19. 19.Find the value of x² − 2xy + y² when x = 11 and y = 5.
20. 20.Use (a + b)(a − b) = a² − b² to find 35 × 25.
21. 21.Use a² − b² = (a + b)(a − b) to find 76² − 31².
22. 22.Use (a − b)² = a² − 2ab + b² to find 27².
23. 23.Use (a + b)(a − b) = a² − b² to find 27 × 13.
24. 24.If a + b = 7 and ab = 10, what is a² + b²?
25. 25.Use (a − b)² = a² − 2ab + b² to find 67².
26. 26.Use a² − b² = (a + b)(a − b) to find 32² − 28².
27. 27.Use a² − b² = (a + b)(a − b) to find 76² − 13².
28. 28.Use (a + b)² = a² + 2ab + b² to find 89².
29. 29.Use (a + b)² = a² + 2ab + b² to find 58².
30. 30.Use (a − b)² = a² − 2ab + b² to find 77².
31. 31.If a − b = 1 and ab = 132, what is a² + b²?
32. 32.Find the value of x² − 2xy + y² when x = 6 and y = 5.
33. 33.Use (a + b)(a − b) = a² − b² to find 23 × 17.
34. 34.Find the value of x² + 2xy + y² when x = 7 and y = 5.
35. 35.Find the value of x² − y² when x = 15 and y = 2.
36. 36.Use (a − b)² = a² − 2ab + b² to find 23².
37. 37.Use (a + b)² = a² + 2ab + b² to find 68².
38. 38.Use a² − b² = (a + b)(a − b) to find 50² − 41².
39. 39.Use (a + b)² = a² + 2ab + b² to find 23².
40. 40.Use (a + b)(a − b) = a² − b² to find 26 × 14.

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