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 + 2xy + y² when x = 3 and y = 2.
- 2.Use a² − b² = (a + b)(a − b) to find 48² − 37².
- 3.Use (a + b)(a − b) = a² − b² to find 84 × 76.
- 4.Use (a + b)² = a² + 2ab + b² to find 61².
- 5.Use (a − b)² = a² − 2ab + b² to find 35².
- 6.Use (a + b)(a − b) = a² − b² to find 23 × 17.
- 7.Find the value of x² − y² when x = 13 and y = 1.
- 8.Use (a − b)² = a² − 2ab + b² to find 97².
- 9.Use (a − b)² = a² − 2ab + b² to find 65².
- 10.Use (a + b)² = a² + 2ab + b² to find 51².
- 11.Use a² − b² = (a + b)(a − b) to find 53² − 12².
- 12.Use (a + b)(a − b) = a² − b² to find 109 × 91.
- 13.Use (a + b)(a − b) = a² − b² to find 98 × 82.
- 14.Use (a + b)² = a² + 2ab + b² to find 29².
- 15.Use (a + b)(a − b) = a² − b² to find 71 × 69.
- 16.If a + b = 5 and ab = 4, what is a² + b²?
- 17.Use a² − b² = (a + b)(a − b) to find 82² − 17².
- 18.Find the value of x² + 2xy + y² when x = 7 and y = 5.
- 19.Use (a + b)(a − b) = a² − b² to find 97 × 83.
- 20.Use (a + b)(a − b) = a² − b² to find 83 × 77.
- 21.If a + b = 13 and ab = 12, what is a² + b²?
- 22.Use a² − b² = (a + b)(a − b) to find 49² − 45².
- 23.If a − b = 1 and ab = 2, what is a² + b²?
- 24.Use (a + b)² = a² + 2ab + b² to find 93².
- 25.Use (a + b)² = a² + 2ab + b² to find 87².
- 26.Use a² − b² = (a + b)(a − b) to find 36² − 8².
- 27.Find the value of x² − 2xy + y² when x = 13 and y = 9.
- 28.If a − b = 5 and ab = 66, what is a² + b²?
- 29.Use (a + b)(a − b) = a² − b² to find 53 × 47.
- 30.Find the value of x² − 2xy + y² when x = 7 and y = 2.
- 31.If a − b = 7 and ab = 30, what is a² + b²?
- 32.Find the value of x² + 2xy + y² when x = 4 and y = 3.
- 33.Use (a − b)² = a² − 2ab + b² to find 67².
- 34.Find the value of x² − y² when x = 4 and y = 1.
- 35.Find the value of x² − y² when x = 7 and y = 4.
- 36.Use a² − b² = (a + b)(a − b) to find 73² − 48².
- 37.Find the value of x² + 2xy + y² when x = 9 and y = 3.
- 38.Find the value of x² + 2xy + y² when x = 15 and y = 5.
- 39.Use (a − b)² = a² − 2ab + b² to find 38².
- 40.If a − b = 2 and ab = 63, what is a² + b²?
Answer key
- 25
- 935
- 6384
- 3721
- 1225
- 391
- 168
- 9409
- 4225
- 2601
- 2665
- 9919
- 8036
- 841
- 4899
- 17
- 6435
- 144
- 8051
- 6391
- 145
- 376
- 5
- 8649
- 7569
- 1232
- 16
- 157
- 2491
- 25
- 109
- 49
- 4489
- 15
- 33
- 3025
- 144
- 400
- 1444
- 130
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets