Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 12 · 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 89².
2. 2.If a − b = 3 and ab = 4, what is a² + b²?
3. 3.Use (a + b)² = a² + 2ab + b² to find 12².
4. 4.Use (a + b)² = a² + 2ab + b² to find 103².
5. 5.Use (a − b)² = a² − 2ab + b² to find 57².
6. 6.If a + b = 10 and ab = 24, what is a² + b²?
7. 7.Use (a − b)² = a² − 2ab + b² to find 28².
8. 8.Use a² − b² = (a + b)(a − b) to find 45² − 4².
9. 9.Use a² − b² = (a + b)(a − b) to find 43² − 18².
10. 10.Use (a + b)(a − b) = a² − b² to find 55 × 45.
11. 11.Use (a − b)² = a² − 2ab + b² to find 71².
12. 12.Find the value of x² − 2xy + y² when x = 12 and y = 7.
13. 13.Use (a − b)² = a² − 2ab + b² to find 67².
14. 14.Use a² − b² = (a + b)(a − b) to find 76² − 68².
15. 15.Find the value of x² + 2xy + y² when x = 9 and y = 2.
16. 16.Find the value of x² − 2xy + y² when x = 15 and y = 14.
17. 17.Use (a + b)² = a² + 2ab + b² to find 37².
18. 18.Use a² − b² = (a + b)(a − b) to find 63² − 42².
19. 19.If a + b = 13 and ab = 40, what is a² + b²?
20. 20.Use a² − b² = (a + b)(a − b) to find 88² − 54².
21. 21.If a + b = 3 and ab = 2, what is a² + b²?
22. 22.Use (a − b)² = a² − 2ab + b² to find 63².
23. 23.Use (a + b)(a − b) = a² − b² to find 103 × 97.
24. 24.Use (a − b)² = a² − 2ab + b² to find 74².
25. 25.If a + b = 5 and ab = 6, what is a² + b²?
26. 26.Use a² − b² = (a + b)(a − b) to find 43² − 17².
27. 27.Find the value of x² − 2xy + y² when x = 5 and y = 4.
28. 28.Find the value of x² + 2xy + y² when x = 8 and y = 7.
29. 29.Use a² − b² = (a + b)(a − b) to find 91² − 87².
30. 30.Use a² − b² = (a + b)(a − b) to find 50² − 19².
31. 31.Use a² − b² = (a + b)(a − b) to find 44² − 4².
32. 32.Find the value of x² − y² when x = 3 and y = 1.
33. 33.Use (a + b)(a − b) = a² − b² to find 72 × 68.
34. 34.Use a² − b² = (a + b)(a − b) to find 60² − 48².
35. 35.Use a² − b² = (a + b)(a − b) to find 94² − 27².
36. 36.Use (a − b)² = a² − 2ab + b² to find 21².
37. 37.Use (a + b)² = a² + 2ab + b² to find 95².
38. 38.Use (a + b)(a − b) = a² − b² to find 24 × 16.
39. 39.If a − b = 9 and ab = 10, what is a² + b²?
40. 40.Use a² − b² = (a + b)(a − b) to find 69² − 25².

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