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 53².
- 2.Use (a + b)² = a² + 2ab + b² to find 93².
- 3.Use (a − b)² = a² − 2ab + b² to find 13².
- 4.Use (a + b)² = a² + 2ab + b² to find 86².
- 5.Use (a + b)² = a² + 2ab + b² to find 74².
- 6.Use (a + b)(a − b) = a² − b² to find 62 × 58.
- 7.If a − b = 4 and ab = 5, what is a² + b²?
- 8.Use a² − b² = (a + b)(a − b) to find 41² − 13².
- 9.Use (a − b)² = a² − 2ab + b² to find 59².
- 10.Use (a + b)² = a² + 2ab + b² to find 13².
- 11.Use (a + b)(a − b) = a² − b² to find 31 × 29.
- 12.Use (a + b)² = a² + 2ab + b² to find 67².
- 13.Use a² − b² = (a + b)(a − b) to find 46² − 35².
- 14.Use (a + b)(a − b) = a² − b² to find 67 × 53.
- 15.Use (a + b)² = a² + 2ab + b² to find 29².
- 16.Use a² − b² = (a + b)(a − b) to find 75² − 45².
- 17.Use (a − b)² = a² − 2ab + b² to find 29².
- 18.If a − b = 1 and ab = 12, what is a² + b²?
- 19.Use (a + b)(a − b) = a² − b² to find 58 × 42.
- 20.Use a² − b² = (a + b)(a − b) to find 93² − 2².
- 21.Use a² − b² = (a + b)(a − b) to find 33² − 4².
- 22.Use (a − b)² = a² − 2ab + b² to find 42².
- 23.Use (a + b)² = a² + 2ab + b² to find 19².
- 24.If a + b = 17 and ab = 72, what is a² + b²?
- 25.Use (a + b)(a − b) = a² − b² to find 87 × 73.
- 26.Use (a − b)² = a² − 2ab + b² to find 23².
- 27.If a − b = 8 and ab = 33, what is a² + b²?
- 28.If a + b = 13 and ab = 22, what is a² + b²?
- 29.Find the value of x² − 2xy + y² when x = 8 and y = 7.
- 30.Use (a + b)(a − b) = a² − b² to find 106 × 94.
- 31.Find the value of x² − 2xy + y² when x = 4 and y = 3.
- 32.Use a² − b² = (a + b)(a − b) to find 68² − 39².
- 33.Use (a + b)(a − b) = a² − b² to find 109 × 91.
- 34.If a − b = 2 and ab = 3, what is a² + b²?
- 35.Use (a − b)² = a² − 2ab + b² to find 66².
- 36.Find the value of x² − y² when x = 3 and y = 2.
- 37.Use (a − b)² = a² − 2ab + b² to find 49².
- 38.Use (a − b)² = a² − 2ab + b² to find 15².
- 39.Use (a − b)² = a² − 2ab + b² to find 62².
- 40.Find the value of x² − 2xy + y² when x = 8 and y = 3.
Answer key
- 2809
- 8649
- 169
- 7396
- 5476
- 3596
- 26
- 1512
- 3481
- 169
- 899
- 4489
- 891
- 3551
- 841
- 3600
- 841
- 25
- 2436
- 8645
- 1073
- 1764
- 361
- 145
- 6351
- 529
- 130
- 125
- 1
- 9964
- 1
- 3103
- 9919
- 10
- 4356
- 5
- 2401
- 225
- 3844
- 25
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets