Equations are math statements that express two sides as being equal or the same value. You can remember the concept of equal by looking at the root of the word in "equations" (equa or equal). Equations are simply short-hand math. They are great methods for setting up and even solving common everyday math problems. We write math phrases using variables which can be known or unknown values. The anatomy of a basic equation consists of two parts which are variables and constants. In the problem 9 + x = 11, the integers (9 and 11) are constants and the unknown (x) is the variable.
Equations can be in written in a variety of ways including a) numerical expression form such as "the sum of 6 and 2". b) algebraic expressions such as "6 + x = 8". In most cases we are looking for a variable that is unknown.