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 54².
- 2.Use (a + b)² = a² + 2ab + b² to find 99².
- 3.Use (a − b)² = a² − 2ab + b² to find 48².
- 4.Use a² − b² = (a + b)(a − b) to find 81² − 37².
- 5.Find the value of x² − 2xy + y² when x = 3 and y = 2.
- 6.Use (a − b)² = a² − 2ab + b² to find 51².
- 7.If a + b = 4 and ab = 3, what is a² + b²?
- 8.Use (a − b)² = a² − 2ab + b² to find 89².
- 9.Use a² − b² = (a + b)(a − b) to find 57² − 19².
- 10.Use (a − b)² = a² − 2ab + b² to find 12².
- 11.Use (a + b)(a − b) = a² − b² to find 42 × 38.
- 12.Use (a + b)(a − b) = a² − b² to find 98 × 82.
- 13.Find the value of x² + 2xy + y² when x = 9 and y = 2.
- 14.Use (a + b)² = a² + 2ab + b² to find 32².
- 15.Find the value of x² + 2xy + y² when x = 6 and y = 4.
- 16.If a − b = 3 and ab = 4, what is a² + b²?
- 17.Use (a + b)(a − b) = a² − b² to find 109 × 91.
- 18.Use a² − b² = (a + b)(a − b) to find 58² − 45².
- 19.Find the value of x² − y² when x = 7 and y = 4.
- 20.Use (a + b)(a − b) = a² − b² to find 84 × 76.
- 21.Use (a − b)² = a² − 2ab + b² to find 64².
- 22.Use (a + b)(a − b) = a² − b² to find 35 × 25.
- 23.Use a² − b² = (a + b)(a − b) to find 62² − 26².
- 24.Use (a + b)(a − b) = a² − b² to find 92 × 88.
- 25.Use (a + b)² = a² + 2ab + b² to find 15².
- 26.Find the value of x² + 2xy + y² when x = 8 and y = 2.
- 27.Find the value of x² − y² when x = 5 and y = 4.
- 28.Use (a + b)(a − b) = a² − b² to find 93 × 87.
- 29.Find the value of x² − y² when x = 4 and y = 3.
- 30.Find the value of x² + 2xy + y² when x = 13 and y = 3.
- 31.If a − b = 2 and ab = 3, what is a² + b²?
- 32.Find the value of x² − 2xy + y² when x = 10 and y = 9.
- 33.Use (a + b)² = a² + 2ab + b² to find 63².
- 34.Use (a + b)(a − b) = a² − b² to find 31 × 29.
- 35.Find the value of x² − 2xy + y² when x = 14 and y = 3.
- 36.Use (a + b)² = a² + 2ab + b² to find 41².
- 37.Use a² − b² = (a + b)(a − b) to find 46² − 8².
- 38.Use (a + b)² = a² + 2ab + b² to find 21².
- 39.Find the value of x² − y² when x = 5 and y = 1.
- 40.Use (a + b)² = a² + 2ab + b² to find 71².
Answer key
- 2916
- 9801
- 2304
- 5192
- 1
- 2601
- 10
- 7921
- 2888
- 144
- 1596
- 8036
- 121
- 1024
- 100
- 17
- 9919
- 1339
- 33
- 6384
- 4096
- 875
- 3168
- 8096
- 225
- 100
- 9
- 8091
- 7
- 256
- 10
- 1
- 3969
- 899
- 121
- 1681
- 2052
- 441
- 24
- 5041
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets