An equation is a mathematical statement such that the expression on the left
side of the equals sign (=) has the same value as the expression on the right side.
An example of an equation is 6000 - 4000 = 2000.
One of the terms in an equation may not be know and needs to be determined. Often
this unknown term is represented by a letter such as x. (e.g. x - 4000 = 2000).
The solution of an equation is finding the value of the unknown x. To find the
value of x we can use the additive equation property which says: The two sides of an
equation remain equal if the same number is added to each side.
Example:
x - 5000 = 7000
x - 5000 + 5000 = 7000 + 5000
x - 0 = 12000
x = 12000
Check the answer by substituting the value of x (12000) back into the equation.
12000 - 5000 = 7000