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 = 13 and y = 9.
- 2.Use (a + b)² = a² + 2ab + b² to find 35².
- 3.Use a² − b² = (a + b)(a − b) to find 70² − 52².
- 4.Use (a + b)² = a² + 2ab + b² to find 104².
- 5.If a + b = 16 and ab = 63, what is a² + b²?
- 6.Use (a + b)² = a² + 2ab + b² to find 73².
- 7.Use (a + b)² = a² + 2ab + b² to find 24².
- 8.If a − b = 10 and ab = 11, what is a² + b²?
- 9.Use a² − b² = (a + b)(a − b) to find 87² − 1².
- 10.If a − b = 1 and ab = 12, what is a² + b²?
- 11.Use a² − b² = (a + b)(a − b) to find 38² − 23².
- 12.Use (a + b)(a − b) = a² − b² to find 49 × 31.
- 13.Use (a + b)² = a² + 2ab + b² to find 45².
- 14.Use (a + b)(a − b) = a² − b² to find 53 × 47.
- 15.Use a² − b² = (a + b)(a − b) to find 83² − 62².
- 16.Use (a − b)² = a² − 2ab + b² to find 91².
- 17.Use (a + b)² = a² + 2ab + b² to find 21².
- 18.Use (a − b)² = a² − 2ab + b² to find 95².
- 19.Use (a − b)² = a² − 2ab + b² to find 77².
- 20.Use (a − b)² = a² − 2ab + b² to find 19².
- 21.Use a² − b² = (a + b)(a − b) to find 54² − 42².
- 22.Use (a + b)² = a² + 2ab + b² to find 34².
- 23.Use a² − b² = (a + b)(a − b) to find 41² − 20².
- 24.Use (a + b)² = a² + 2ab + b² to find 56².
- 25.Use a² − b² = (a + b)(a − b) to find 24² − 1².
- 26.Use (a + b)(a − b) = a² − b² to find 67 × 53.
- 27.If a + b = 16 and ab = 60, what is a² + b²?
- 28.Use (a + b)² = a² + 2ab + b² to find 64².
- 29.Use (a + b)(a − b) = a² − b² to find 62 × 58.
- 30.Find the value of x² + 2xy + y² when x = 13 and y = 4.
- 31.Use (a + b)(a − b) = a² − b² to find 101 × 99.
- 32.Use (a + b)² = a² + 2ab + b² to find 39².
- 33.Use a² − b² = (a + b)(a − b) to find 84² − 44².
- 34.If a − b = 4 and ab = 60, what is a² + b²?
- 35.Find the value of x² + 2xy + y² when x = 10 and y = 6.
- 36.Use a² − b² = (a + b)(a − b) to find 61² − 24².
- 37.Use (a − b)² = a² − 2ab + b² to find 98².
- 38.Find the value of x² + 2xy + y² when x = 4 and y = 3.
- 39.Use (a − b)² = a² − 2ab + b² to find 44².
- 40.Find the value of x² + 2xy + y² when x = 3 and y = 1.
Answer key
- 16
- 1225
- 2196
- 10816
- 130
- 5329
- 576
- 122
- 7568
- 25
- 915
- 1519
- 2025
- 2491
- 3045
- 8281
- 441
- 9025
- 5929
- 361
- 1152
- 1156
- 1281
- 3136
- 575
- 3551
- 136
- 4096
- 3596
- 289
- 9999
- 1521
- 5120
- 136
- 256
- 3145
- 9604
- 49
- 1936
- 16
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets