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 83².
- 2.Find the value of x² + 2xy + y² when x = 6 and y = 3.
- 3.Use (a − b)² = a² − 2ab + b² to find 87².
- 4.If a − b = 4 and ab = 5, what is a² + b²?
- 5.Use (a + b)(a − b) = a² − b² to find 26 × 14.
- 6.If a − b = 1 and ab = 42, what is a² + b²?
- 7.Use a² − b² = (a + b)(a − b) to find 83² − 73².
- 8.Use a² − b² = (a + b)(a − b) to find 88² − 69².
- 9.Use a² − b² = (a + b)(a − b) to find 96² − 75².
- 10.Use (a − b)² = a² − 2ab + b² to find 17².
- 11.Use (a − b)² = a² − 2ab + b² to find 36².
- 12.Use a² − b² = (a + b)(a − b) to find 99² − 3².
- 13.Use (a + b)(a − b) = a² − b² to find 23 × 17.
- 14.Use a² − b² = (a + b)(a − b) to find 91² − 17².
- 15.Use (a + b)(a − b) = a² − b² to find 49 × 31.
- 16.Use (a + b)² = a² + 2ab + b² to find 106².
- 17.Find the value of x² − 2xy + y² when x = 11 and y = 7.
- 18.Use a² − b² = (a + b)(a − b) to find 50² − 3².
- 19.Use (a + b)² = a² + 2ab + b² to find 56².
- 20.Use (a + b)(a − b) = a² − b² to find 55 × 45.
- 21.Use (a + b)(a − b) = a² − b² to find 24 × 16.
- 22.Use (a + b)² = a² + 2ab + b² to find 94².
- 23.Use (a + b)(a − b) = a² − b² to find 58 × 42.
- 24.If a − b = 9 and ab = 10, what is a² + b²?
- 25.Use (a + b)(a − b) = a² − b² to find 73 × 67.
- 26.If a + b = 6 and ab = 8, what is a² + b²?
- 27.Find the value of x² + 2xy + y² when x = 11 and y = 1.
- 28.Use (a + b)² = a² + 2ab + b² to find 41².
- 29.Use (a − b)² = a² − 2ab + b² to find 96².
- 30.Use a² − b² = (a + b)(a − b) to find 93² − 43².
- 31.Use a² − b² = (a + b)(a − b) to find 89² − 83².
- 32.Find the value of x² + 2xy + y² when x = 10 and y = 5.
- 33.Use a² − b² = (a + b)(a − b) to find 61² − 31².
- 34.Use (a − b)² = a² − 2ab + b² to find 11².
- 35.Find the value of x² − y² when x = 13 and y = 7.
- 36.Use a² − b² = (a + b)(a − b) to find 35² − 5².
- 37.Use (a − b)² = a² − 2ab + b² to find 75².
- 38.Use (a + b)² = a² + 2ab + b² to find 83².
- 39.Use (a + b)(a − b) = a² − b² to find 47 × 33.
- 40.Use (a + b)² = a² + 2ab + b² to find 35².
Answer key
- 6889
- 81
- 7569
- 26
- 364
- 85
- 1560
- 2983
- 3591
- 289
- 1296
- 9792
- 391
- 7992
- 1519
- 11236
- 16
- 2491
- 3136
- 2475
- 384
- 8836
- 2436
- 101
- 4891
- 20
- 144
- 1681
- 9216
- 6800
- 1032
- 225
- 2760
- 121
- 120
- 1200
- 5625
- 6889
- 1551
- 1225
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets