Algebra worksheet for substituting values into expressions, including sections for variables a, b, x, and y.

- Section A:
- Expression: 4 + 2a, Value of a: a = 6, Calculation: 4 + 2 × 6 = 4 + 12, Value of expression: 16
- Expression: a/5 + 20, Value of a: a = 10, Calculation: 10 ÷ 5 + 20 = 2 + 20, Value of expression: 22
- Expression: 11 - a/3, Value of a: a = 12, Calculation: 11 - 12 ÷ 3 = 11 - 4, Value of expression: 7
- Expression: 8a/10, Value of a: a = 5, Calculation: (8 × 5) ÷ 10 = 40 ÷ 10, Value of expression: 4

- Section B:
- Expression: (14b + 13)/9, Value of b: b = 1, Calculation: (14 × 1 + 13) ÷ 9 = 27 ÷ 9, Value of expression: 3
- Expression: (52 - 2b)/7, Value of b: b = 12, Calculation: (52 - 2 × 12) ÷ 7 = (52 - 24) ÷ 7 = 28 ÷ 7, Value of expression: 4
- Expression: 10b - b², Value of b: b = 2, Calculation: 10 × 2 - 2² = 20 - 4, Value of expression: 16

- Section C:
- Expression: 7x + xy, Value of x and y: x = 2, y = 3, Calculation: 7 × 2 + 2 × 3 = 14 + 6, Value of expression: 20
- Expression: 9y - 6x, Value of x and y: x = 5, y = 8, Calculation: 9 × 8 - 6 × 5 = 72 - 30, Value of expression: 42
- Expression: x² + y², Value of x and y: x = 11, y = 4, Calculation: 11² + 4² = 121 + 16, Value of expression: 137
- Expression: (84 - 6x)/y, Value of x and y: x = 10, y = 3, Calculation: (84 - 6 × 10) ÷ 3 = (84 - 60) ÷ 3 = 24 ÷ 3, Value of expression: 8
- Expression: (x + y)² + 3, Value of x and y: x = 2, y = 5, Calculation: (2 + 5)² + 3 = 7² + 3 = 49 + 3, Value of expression: 52
- Expression: (33 - 3x)/(2y), Value of x and y: x = 7, y = 3, Calculation: (33 - 3 × 7) ÷ (2 × 3) = (33 - 21) ÷ 6 = 12 ÷ 6, Value of expression: 2
- Expression: xy - y², Value of x and y: x = 10, y = 6, Calculation: 10 × 6 - 6² = 60 - 36, Value of expression: 24
- Expression: (xy - 3y)², Value of x and y: x = 4, y = 8, Calculation: (4 × 8 - 3 × 8)² = (32 - 24)² = 8², Value of expression: 64