Definition of dray. : a vehicle used to haul goods; especially : a strong cart or wagon without sides.
Expressions versus Equations. A difference between expressions and equations is what each represents. An expression shows a math relationship. One key to an expression is that there is no solution. An expression does not have an answer. An expression, however, can be evaluated. To evaluate an expression, substitute values for the variables.
Originally Answered: What is the difference between formulas and equations? A formula is usually a general rule, written in the form of algebra (letters to represent different quantities) to more easily and succinctly portray the information. That whole thing can be written as [math]F=ma[/math], which means exactly the same thing. An equation is any mathematical text that has an equal sign.