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 103².
- 2.Use (a − b)² = a² − 2ab + b² to find 62².
- 3.Use a² − b² = (a + b)(a − b) to find 85² − 79².
- 4.Find the value of x² − 2xy + y² when x = 11 and y = 2.
- 5.Use (a − b)² = a² − 2ab + b² to find 22².
- 6.Use (a − b)² = a² − 2ab + b² to find 36².
- 7.Find the value of x² + 2xy + y² when x = 7 and y = 4.
- 8.If a − b = 4 and ab = 5, what is a² + b²?
- 9.Find the value of x² − y² when x = 14 and y = 3.
- 10.Find the value of x² − y² when x = 13 and y = 6.
- 11.Use a² − b² = (a + b)(a − b) to find 68² − 35².
- 12.If a + b = 11 and ab = 28, what is a² + b²?
- 13.Use (a + b)² = a² + 2ab + b² to find 97².
- 14.Find the value of x² − y² when x = 3 and y = 2.
- 15.Use (a + b)(a − b) = a² − b² to find 38 × 22.
- 16.If a + b = 18 and ab = 80, what is a² + b²?
- 17.Use (a − b)² = a² − 2ab + b² to find 76².
- 18.Use (a + b)(a − b) = a² − b² to find 73 × 67.
- 19.Use (a + b)(a − b) = a² − b² to find 63 × 57.
- 20.Use (a + b)(a − b) = a² − b² to find 35 × 25.
- 21.Use (a − b)² = a² − 2ab + b² to find 87².
- 22.Find the value of x² − 2xy + y² when x = 13 and y = 10.
- 23.Use (a + b)(a − b) = a² − b² to find 99 × 81.
- 24.Use a² − b² = (a + b)(a − b) to find 57² − 32².
- 25.Find the value of x² + 2xy + y² when x = 11 and y = 7.
- 26.Use (a + b)(a − b) = a² − b² to find 55 × 45.
- 27.Use a² − b² = (a + b)(a − b) to find 35² − 34².
- 28.If a + b = 10 and ab = 21, what is a² + b²?
- 29.If a + b = 6 and ab = 8, what is a² + b²?
- 30.Use (a + b)(a − b) = a² − b² to find 65 × 55.
- 31.Find the value of x² − 2xy + y² when x = 5 and y = 1.
- 32.Use a² − b² = (a + b)(a − b) to find 68² − 57².
- 33.If a − b = 2 and ab = 3, what is a² + b²?
- 34.Use (a − b)² = a² − 2ab + b² to find 37².
- 35.Use a² − b² = (a + b)(a − b) to find 97² − 90².
- 36.Find the value of x² + 2xy + y² when x = 4 and y = 3.
- 37.Use a² − b² = (a + b)(a − b) to find 51² − 21².
- 38.Use (a − b)² = a² − 2ab + b² to find 19².
- 39.Find the value of x² − 2xy + y² when x = 6 and y = 3.
- 40.Use (a + b)(a − b) = a² − b² to find 44 × 36.
Answer key
- 10609
- 3844
- 984
- 81
- 484
- 1296
- 121
- 26
- 187
- 133
- 3399
- 65
- 9409
- 5
- 836
- 164
- 5776
- 4891
- 3591
- 875
- 7569
- 9
- 8019
- 2225
- 324
- 2475
- 69
- 58
- 20
- 3575
- 16
- 1375
- 10
- 1369
- 1309
- 49
- 2160
- 361
- 9
- 1584
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets