Class 8 Maths Worksheet: Algebraic Identities

Maths worksheets lesson 61: Algebraic identities · Set 461 · 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 = 5 and ab = 50, what is a² + b²?
2. 2.Use (a + b)² = a² + 2ab + b² to find 21².
3. 3.Use a² − b² = (a + b)(a − b) to find 35² − 32².
4. 4.If a + b = 8 and ab = 15, what is a² + b²?
5. 5.Use (a + b)(a − b) = a² − b² to find 32 × 28.
6. 6.Use (a + b)² = a² + 2ab + b² to find 44².
7. 7.Use (a + b)(a − b) = a² − b² to find 65 × 55.
8. 8.If a + b = 5 and ab = 6, what is a² + b²?
9. 9.Find the value of x² − y² when x = 7 and y = 5.
10. 10.Use (a − b)² = a² − 2ab + b² to find 14².
11. 11.Use a² − b² = (a + b)(a − b) to find 72² − 67².
12. 12.Use (a + b)(a − b) = a² − b² to find 93 × 87.
13. 13.Use (a + b)² = a² + 2ab + b² to find 36².
14. 14.Find the value of x² − y² when x = 13 and y = 5.
15. 15.Use (a + b)(a − b) = a² − b² to find 46 × 34.
16. 16.Use (a + b)² = a² + 2ab + b² to find 14².
17. 17.Use (a + b)² = a² + 2ab + b² to find 26².
18. 18.Use a² − b² = (a + b)(a − b) to find 58² − 44².
19. 19.Use (a + b)(a − b) = a² − b² to find 45 × 35.
20. 20.Use (a − b)² = a² − 2ab + b² to find 58².
21. 21.Use (a + b)(a − b) = a² − b² to find 73 × 67.
22. 22.If a − b = 1 and ab = 2, what is a² + b²?
23. 23.Find the value of x² − 2xy + y² when x = 3 and y = 2.
24. 24.Find the value of x² − 2xy + y² when x = 10 and y = 7.
25. 25.Use (a + b)(a − b) = a² − b² to find 36 × 24.
26. 26.Use (a + b)² = a² + 2ab + b² to find 104².
27. 27.Use (a + b)² = a² + 2ab + b² to find 28².
28. 28.Use (a − b)² = a² − 2ab + b² to find 36².
29. 29.Use (a + b)(a − b) = a² − b² to find 69 × 51.
30. 30.Use (a + b)(a − b) = a² − b² to find 63 × 57.
31. 31.Use (a − b)² = a² − 2ab + b² to find 67².
32. 32.Use (a + b)(a − b) = a² − b² to find 22 × 18.
33. 33.Use (a − b)² = a² − 2ab + b² to find 26².
34. 34.Find the value of x² + 2xy + y² when x = 3 and y = 2.
35. 35.Use (a + b)(a − b) = a² − b² to find 85 × 75.
36. 36.If a + b = 19 and ab = 88, what is a² + b²?
37. 37.Use (a + b)(a − b) = a² − b² to find 34 × 26.
38. 38.If a + b = 16 and ab = 55, what is a² + b²?
39. 39.Use (a − b)² = a² − 2ab + b² to find 65².
40. 40.Use (a − b)² = a² − 2ab + b² to find 32².

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