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)(a − b) = a² − b² to find 103 × 97.
- 2.Use a² − b² = (a + b)(a − b) to find 40² − 4².
- 3.Use (a + b)² = a² + 2ab + b² to find 95².
- 4.If a + b = 14 and ab = 40, what is a² + b²?
- 5.Use (a − b)² = a² − 2ab + b² to find 59².
- 6.Use (a + b)² = a² + 2ab + b² to find 59².
- 7.Find the value of x² + 2xy + y² when x = 14 and y = 12.
- 8.Use (a − b)² = a² − 2ab + b² to find 67².
- 9.Use (a − b)² = a² − 2ab + b² to find 28².
- 10.Use (a − b)² = a² − 2ab + b² to find 82².
- 11.Use (a − b)² = a² − 2ab + b² to find 23².
- 12.Use (a + b)(a − b) = a² − b² to find 44 × 36.
- 13.Use (a + b)² = a² + 2ab + b² to find 39².
- 14.If a − b = 1 and ab = 6, what is a² + b²?
- 15.If a − b = 1 and ab = 72, what is a² + b²?
- 16.Use (a + b)² = a² + 2ab + b² to find 18².
- 17.Use a² − b² = (a + b)(a − b) to find 94² − 73².
- 18.Use (a + b)² = a² + 2ab + b² to find 24².
- 19.If a + b = 10 and ab = 9, what is a² + b²?
- 20.If a + b = 10 and ab = 21, what is a² + b²?
- 21.Use (a − b)² = a² − 2ab + b² to find 13².
- 22.Use (a + b)² = a² + 2ab + b² to find 88².
- 23.Use a² − b² = (a + b)(a − b) to find 28² − 1².
- 24.Find the value of x² − y² when x = 5 and y = 4.
- 25.Use (a + b)(a − b) = a² − b² to find 86 × 74.
- 26.Find the value of x² − y² when x = 14 and y = 11.
- 27.Use a² − b² = (a + b)(a − b) to find 34² − 5².
- 28.Use (a + b)(a − b) = a² − b² to find 52 × 48.
- 29.Use (a + b)(a − b) = a² − b² to find 23 × 17.
- 30.Use (a + b)² = a² + 2ab + b² to find 92².
- 31.Use (a + b)² = a² + 2ab + b² to find 71².
- 32.Use (a − b)² = a² − 2ab + b² to find 77².
- 33.Find the value of x² + 2xy + y² when x = 10 and y = 9.
- 34.If a + b = 6 and ab = 5, what is a² + b²?
- 35.Use (a + b)² = a² + 2ab + b² to find 32².
- 36.Find the value of x² − 2xy + y² when x = 13 and y = 8.
- 37.Use (a − b)² = a² − 2ab + b² to find 84².
- 38.Find the value of x² − y² when x = 3 and y = 2.
- 39.Use (a + b)² = a² + 2ab + b² to find 51².
- 40.Find the value of x² − 2xy + y² when x = 11 and y = 5.
Answer key
- 9991
- 1584
- 9025
- 116
- 3481
- 3481
- 676
- 4489
- 784
- 6724
- 529
- 1584
- 1521
- 13
- 145
- 324
- 3507
- 576
- 82
- 58
- 169
- 7744
- 783
- 9
- 6364
- 75
- 1131
- 2496
- 391
- 8464
- 5041
- 5929
- 361
- 26
- 1024
- 25
- 7056
- 5
- 2601
- 36
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets