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 = 14 and y = 8.
- 2.Use (a + b)(a − b) = a² − b² to find 101 × 99.
- 3.If a + b = 5 and ab = 4, what is a² + b²?
- 4.Use (a + b)(a − b) = a² − b² to find 82 × 78.
- 5.Find the value of x² − y² when x = 8 and y = 6.
- 6.Use (a + b)² = a² + 2ab + b² to find 47².
- 7.Use (a + b)(a − b) = a² − b² to find 51 × 49.
- 8.Use (a + b)(a − b) = a² − b² to find 64 × 56.
- 9.Use (a − b)² = a² − 2ab + b² to find 28².
- 10.If a + b = 21 and ab = 108, what is a² + b²?
- 11.Use (a + b)(a − b) = a² − b² to find 34 × 26.
- 12.Use (a + b)(a − b) = a² − b² to find 56 × 44.
- 13.Use a² − b² = (a + b)(a − b) to find 92² − 70².
- 14.If a + b = 13 and ab = 42, what is a² + b²?
- 15.Find the value of x² − 2xy + y² when x = 14 and y = 6.
- 16.Use (a + b)(a − b) = a² − b² to find 27 × 13.
- 17.Use (a + b)(a − b) = a² − b² to find 33 × 27.
- 18.Find the value of x² + 2xy + y² when x = 5 and y = 1.
- 19.Find the value of x² + 2xy + y² when x = 5 and y = 4.
- 20.Find the value of x² + 2xy + y² when x = 15 and y = 3.
- 21.Use (a − b)² = a² − 2ab + b² to find 31².
- 22.If a + b = 17 and ab = 66, what is a² + b²?
- 23.Find the value of x² − 2xy + y² when x = 10 and y = 2.
- 24.Find the value of x² − y² when x = 13 and y = 10.
- 25.Find the value of x² + 2xy + y² when x = 13 and y = 12.
- 26.Use (a + b)(a − b) = a² − b² to find 35 × 25.
- 27.Use a² − b² = (a + b)(a − b) to find 29² − 23².
- 28.Find the value of x² − 2xy + y² when x = 7 and y = 2.
- 29.Use (a + b)² = a² + 2ab + b² to find 91².
- 30.Use (a + b)(a − b) = a² − b² to find 73 × 67.
- 31.Use (a + b)² = a² + 2ab + b² to find 75².
- 32.Find the value of x² − y² when x = 6 and y = 2.
- 33.If a + b = 6 and ab = 5, what is a² + b²?
- 34.Use (a + b)(a − b) = a² − b² to find 69 × 51.
- 35.Find the value of x² + 2xy + y² when x = 4 and y = 3.
- 36.If a − b = 3 and ab = 4, what is a² + b²?
- 37.Use a² − b² = (a + b)(a − b) to find 24² − 1².
- 38.Use (a − b)² = a² − 2ab + b² to find 86².
- 39.Use (a + b)(a − b) = a² − b² to find 53 × 47.
- 40.Use (a + b)² = a² + 2ab + b² to find 46².
Answer key
- 36
- 9999
- 17
- 6396
- 28
- 2209
- 2499
- 3584
- 784
- 225
- 884
- 2464
- 3564
- 85
- 64
- 351
- 891
- 36
- 81
- 324
- 961
- 157
- 64
- 69
- 625
- 875
- 312
- 25
- 8281
- 4891
- 5625
- 32
- 26
- 3519
- 49
- 17
- 575
- 7396
- 2491
- 2116
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets