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 − y² when x = 3 and y = 1.
- 2.Use (a − b)² = a² − 2ab + b² to find 86².
- 3.Use (a − b)² = a² − 2ab + b² to find 11².
- 4.Find the value of x² − 2xy + y² when x = 5 and y = 1.
- 5.Use (a + b)² = a² + 2ab + b² to find 28².
- 6.Use (a + b)² = a² + 2ab + b² to find 74².
- 7.Use a² − b² = (a + b)(a − b) to find 35² − 25².
- 8.If a + b = 13 and ab = 12, what is a² + b²?
- 9.Use (a + b)² = a² + 2ab + b² to find 31².
- 10.Use a² − b² = (a + b)(a − b) to find 30² − 25².
- 11.Use (a + b)² = a² + 2ab + b² to find 53².
- 12.Use (a − b)² = a² − 2ab + b² to find 45².
- 13.Use (a + b)² = a² + 2ab + b² to find 64².
- 14.Use (a + b)(a − b) = a² − b² to find 83 × 77.
- 15.Find the value of x² − 2xy + y² when x = 10 and y = 8.
- 16.Find the value of x² − y² when x = 8 and y = 6.
- 17.Use (a − b)² = a² − 2ab + b² to find 52².
- 18.Use (a + b)(a − b) = a² − b² to find 79 × 61.
- 19.Use (a + b)(a − b) = a² − b² to find 91 × 89.
- 20.Find the value of x² + 2xy + y² when x = 11 and y = 2.
- 21.If a − b = 4 and ab = 96, what is a² + b²?
- 22.Use a² − b² = (a + b)(a − b) to find 87² − 14².
- 23.Use a² − b² = (a + b)(a − b) to find 39² − 1².
- 24.Use a² − b² = (a + b)(a − b) to find 84² − 54².
- 25.Find the value of x² − y² when x = 11 and y = 1.
- 26.If a − b = 1 and ab = 6, what is a² + b²?
- 27.Use (a + b)² = a² + 2ab + b² to find 101².
- 28.Use (a + b)(a − b) = a² − b² to find 63 × 57.
- 29.Use (a − b)² = a² − 2ab + b² to find 38².
- 30.Use (a + b)² = a² + 2ab + b² to find 88².
- 31.Use a² − b² = (a + b)(a − b) to find 37² − 33².
- 32.Use (a + b)(a − b) = a² − b² to find 72 × 68.
- 33.Use a² − b² = (a + b)(a − b) to find 71² − 35².
- 34.Find the value of x² + 2xy + y² when x = 3 and y = 2.
- 35.Find the value of x² − y² when x = 10 and y = 4.
- 36.Use (a + b)² = a² + 2ab + b² to find 99².
- 37.Use a² − b² = (a + b)(a − b) to find 51² − 22².
- 38.Use (a − b)² = a² − 2ab + b² to find 43².
- 39.Use (a − b)² = a² − 2ab + b² to find 68².
- 40.Use (a + b)² = a² + 2ab + b² to find 17².
Answer key
- 8
- 7396
- 121
- 16
- 784
- 5476
- 600
- 145
- 961
- 275
- 2809
- 2025
- 4096
- 6391
- 4
- 28
- 2704
- 4819
- 8099
- 169
- 208
- 7373
- 1520
- 4140
- 120
- 13
- 10201
- 3591
- 1444
- 7744
- 280
- 4896
- 3816
- 25
- 84
- 9801
- 2117
- 1849
- 4624
- 289
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets