Question

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Identify the expression as a numerical expression or a variable expression. For a variable expression, name the variable.

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variable expression; d is the variable.


variable expression; i is the variable.


numerical expression


variable expression; there is no variable.

Answer 1

numerical expression

Answer 2

Variable, In algebra, 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).