Meaning of VARIABLE in English
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). Variables should be distinguished from coefficients, fixed values that multiply powers of variables in polynomial s and algebraic equation s. In the quadratic equation a x 2 + b x + c = 0, x is the variable and a , b and c are coefficients whose values must be specified to solve the equation. In translating word problems into algebraic equations, quantities to be determined can be represented by variables.
Britannica Concise Encyclopedia. Краткая энциклопедия Британика. 2012