Class 8 Maths Worksheet: Algebraic Identities
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.
NameDateTime takenScore ___ / 40
- 1.Find the value of x² + 2xy + y² when x = 4 and y = 3.
- 2.Use a² − b² = (a + b)(a − b) to find 90² − 29².
- 3.Use (a − b)² = a² − 2ab + b² to find 61².
- 4.Use (a + b)² = a² + 2ab + b² to find 18².
- 5.Use (a + b)² = a² + 2ab + b² to find 77².
- 6.Use (a + b)² = a² + 2ab + b² to find 11².
- 7.Use a² − b² = (a + b)(a − b) to find 59² − 49².
- 8.If a − b = 3 and ab = 70, what is a² + b²?
- 9.If a − b = 4 and ab = 12, what is a² + b²?
- 10.Find the value of x² + 2xy + y² when x = 11 and y = 8.
- 11.Use (a − b)² = a² − 2ab + b² to find 73².
- 12.Use a² − b² = (a + b)(a − b) to find 98² − 59².
- 13.Use (a − b)² = a² − 2ab + b² to find 16².
- 14.Find the value of x² + 2xy + y² when x = 15 and y = 11.
- 15.If a + b = 3 and ab = 2, what is a² + b²?
- 16.Use (a − b)² = a² − 2ab + b² to find 44².
- 17.Use a² − b² = (a + b)(a − b) to find 23² − 12².
- 18.Use (a + b)(a − b) = a² − b² to find 47 × 33.
- 19.Use (a − b)² = a² − 2ab + b² to find 88².
- 20.Use (a + b)² = a² + 2ab + b² to find 49².
- 21.Use (a + b)² = a² + 2ab + b² to find 12².
- 22.Use (a − b)² = a² − 2ab + b² to find 29².
- 23.Use (a + b)² = a² + 2ab + b² to find 16².
- 24.Use a² − b² = (a + b)(a − b) to find 74² − 62².
- 25.Use (a − b)² = a² − 2ab + b² to find 45².
- 26.Use (a + b)(a − b) = a² − b² to find 105 × 95.
- 27.Find the value of x² + 2xy + y² when x = 3 and y = 2.
- 28.Use (a + b)² = a² + 2ab + b² to find 22².
- 29.Use (a + b)² = a² + 2ab + b² to find 74².
- 30.Use (a + b)(a − b) = a² − b² to find 55 × 45.
- 31.Use (a + b)² = a² + 2ab + b² to find 43².
- 32.Use (a + b)² = a² + 2ab + b² to find 53².
- 33.Use (a + b)(a − b) = a² − b² to find 73 × 67.
- 34.Use (a + b)(a − b) = a² − b² to find 65 × 55.
- 35.Use (a + b)² = a² + 2ab + b² to find 63².
- 36.Use a² − b² = (a + b)(a − b) to find 66² − 9².
- 37.Find the value of x² − y² when x = 5 and y = 3.
- 38.Use (a + b)² = a² + 2ab + b² to find 108².
- 39.If a + b = 15 and ab = 44, what is a² + b²?
- 40.Use (a + b)(a − b) = a² − b² to find 45 × 35.
Answer key
- 49
- 7259
- 3721
- 324
- 5929
- 121
- 1080
- 149
- 40
- 361
- 5329
- 6123
- 256
- 676
- 5
- 1936
- 385
- 1551
- 7744
- 2401
- 144
- 841
- 256
- 1632
- 2025
- 9975
- 25
- 484
- 5476
- 2475
- 1849
- 2809
- 4891
- 3575
- 3969
- 4275
- 16
- 11664
- 137
- 1575
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets