Definition of dray. : a vehicle used to haul goods; especially : a strong cart or wagon without sides.
The main difference between an equation and a function is the fact that an equation usually deals with a single input, whereas, a function can have numerous inputs. In mathematics, an equation is used to denote the equality between two expressions.
Equation. in mathematics, the analytical form of the problem of finding those inputs for which two given functions have equal outputs. The functional inputs are usually called unknowns, and the unknowns for which the functional outputs are equal are called solutions or roots.