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)(a − b) = a² − b² to find 87 × 73.
- 3.Use a² − b² = (a + b)(a − b) to find 56² − 45².
- 4.Use a² − b² = (a + b)(a − b) to find 27² − 2².
- 5.Use a² − b² = (a + b)(a − b) to find 67² − 12².
- 6.Use a² − b² = (a + b)(a − b) to find 97² − 11².
- 7.Find the value of x² − 2xy + y² when x = 10 and y = 9.
- 8.Use (a + b)(a − b) = a² − b² to find 44 × 36.
- 9.Use (a + b)(a − b) = a² − b² to find 92 × 88.
- 10.Use (a + b)(a − b) = a² − b² to find 64 × 56.
- 11.Use a² − b² = (a + b)(a − b) to find 70² − 32².
- 12.If a + b = 13 and ab = 40, what is a² + b²?
- 13.Use (a − b)² = a² − 2ab + b² to find 91².
- 14.If a − b = 4 and ab = 5, what is a² + b²?
- 15.Find the value of x² + 2xy + y² when x = 7 and y = 6.
- 16.Find the value of x² + 2xy + y² when x = 13 and y = 11.
- 17.Use (a + b)(a − b) = a² − b² to find 48 × 32.
- 18.Use (a − b)² = a² − 2ab + b² to find 56².
- 19.Use (a + b)² = a² + 2ab + b² to find 102².
- 20.Find the value of x² − y² when x = 13 and y = 2.
- 21.Use (a − b)² = a² − 2ab + b² to find 49².
- 22.Use a² − b² = (a + b)(a − b) to find 24² − 11².
- 23.Find the value of x² + 2xy + y² when x = 11 and y = 3.
- 24.Use (a + b)² = a² + 2ab + b² to find 41².
- 25.Use (a + b)² = a² + 2ab + b² to find 27².
- 26.If a + b = 4 and ab = 3, what is a² + b²?
- 27.Find the value of x² + 2xy + y² when x = 8 and y = 4.
- 28.Use a² − b² = (a + b)(a − b) to find 81² − 1².
- 29.If a + b = 6 and ab = 8, what is a² + b²?
- 30.Use a² − b² = (a + b)(a − b) to find 89² − 25².
- 31.Use (a + b)² = a² + 2ab + b² to find 44².
- 32.Use (a + b)² = a² + 2ab + b² to find 33².
- 33.Use (a + b)² = a² + 2ab + b² to find 22².
- 34.Use (a + b)² = a² + 2ab + b² to find 67².
- 35.Use (a − b)² = a² − 2ab + b² to find 43².
- 36.Use (a + b)(a − b) = a² − b² to find 69 × 51.
- 37.Use a² − b² = (a + b)(a − b) to find 40² − 18².
- 38.Use (a + b)(a − b) = a² − b² to find 43 × 37.
- 39.Use (a + b)² = a² + 2ab + b² to find 92².
- 40.Use (a + b)(a − b) = a² − b² to find 51 × 49.
Answer key
- 2916
- 6351
- 1111
- 725
- 4345
- 9288
- 1
- 1584
- 8096
- 3584
- 3876
- 89
- 8281
- 26
- 169
- 576
- 1536
- 3136
- 10404
- 165
- 2401
- 455
- 196
- 1681
- 729
- 10
- 144
- 6560
- 20
- 7296
- 1936
- 1089
- 484
- 4489
- 1849
- 3519
- 1276
- 1591
- 8464
- 2499
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets