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.Use (a − b)² = a² − 2ab + b² to find 88².
- 2.Find the value of x² − 2xy + y² when x = 4 and y = 1.
- 3.Use (a − b)² = a² − 2ab + b² to find 39².
- 4.Find the value of x² + 2xy + y² when x = 11 and y = 8.
- 5.If a − b = 1 and ab = 6, what is a² + b²?
- 6.Use (a − b)² = a² − 2ab + b² to find 48².
- 7.Use (a − b)² = a² − 2ab + b² to find 75².
- 8.Use (a + b)² = a² + 2ab + b² to find 72².
- 9.Use (a + b)² = a² + 2ab + b² to find 41².
- 10.Use (a + b)² = a² + 2ab + b² to find 104².
- 11.Use (a + b)(a − b) = a² − b² to find 83 × 77.
- 12.Use a² − b² = (a + b)(a − b) to find 42² − 4².
- 13.Use (a − b)² = a² − 2ab + b² to find 41².
- 14.Use (a + b)² = a² + 2ab + b² to find 93².
- 15.Use (a − b)² = a² − 2ab + b² to find 95².
- 16.Use (a − b)² = a² − 2ab + b² to find 66².
- 17.Use (a + b)² = a² + 2ab + b² to find 52².
- 18.Use (a − b)² = a² − 2ab + b² to find 57².
- 19.Use (a + b)² = a² + 2ab + b² to find 48².
- 20.Use (a + b)(a − b) = a² − b² to find 41 × 39.
- 21.Use a² − b² = (a + b)(a − b) to find 72² − 34².
- 22.If a − b = 6 and ab = 16, what is a² + b²?
- 23.Use (a + b)(a − b) = a² − b² to find 63 × 57.
- 24.Use (a + b)(a − b) = a² − b² to find 65 × 55.
- 25.Use a² − b² = (a + b)(a − b) to find 43² − 31².
- 26.If a − b = 6 and ab = 27, what is a² + b²?
- 27.Use (a − b)² = a² − 2ab + b² to find 78².
- 28.Use (a + b)² = a² + 2ab + b² to find 34².
- 29.Find the value of x² + 2xy + y² when x = 5 and y = 3.
- 30.Use (a + b)(a − b) = a² − b² to find 84 × 76.
- 31.Use (a + b)² = a² + 2ab + b² to find 92².
- 32.Use (a − b)² = a² − 2ab + b² to find 22².
- 33.Use a² − b² = (a + b)(a − b) to find 83² − 2².
- 34.Use a² − b² = (a + b)(a − b) to find 46² − 8².
- 35.Use (a − b)² = a² − 2ab + b² to find 37².
- 36.If a − b = 1 and ab = 2, what is a² + b²?
- 37.Use (a − b)² = a² − 2ab + b² to find 16².
- 38.Use (a + b)(a − b) = a² − b² to find 55 × 45.
- 39.Use (a − b)² = a² − 2ab + b² to find 26².
- 40.Use (a + b)² = a² + 2ab + b² to find 28².
Answer key
- 7744
- 9
- 1521
- 361
- 13
- 2304
- 5625
- 5184
- 1681
- 10816
- 6391
- 1748
- 1681
- 8649
- 9025
- 4356
- 2704
- 3249
- 2304
- 1599
- 4028
- 68
- 3591
- 3575
- 888
- 90
- 6084
- 1156
- 64
- 6384
- 8464
- 484
- 6885
- 2052
- 1369
- 5
- 256
- 2475
- 676
- 784
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets