Directions: A. Determine the variable(s) in each algebraic expression Write your answers on the blank. 1 52 +7 2) 4 (c + d) 3) (x - 5) + y 45 w 5) (6 + e) - 2

1. z
2. c and d
3. x and y
4. w
5. e
Is a symbol (usually a letter) standing in for an unknown numerical value in an equation. Commonly used variables include x and y (real-number unknowns), z (complex-number unknowns), t (time), r (radius), and s (arc length).