Basics

When we want to work with a number we don't know, we often use a letter instead. We call this number variable or unknown, if we are interested in calculating its value.

For example: 3x is triple x, x/2 is half of x...

A algebraic expression is a combination of variables and numbers using mathematical operations of addition, subtraction, multiplication, division and powers. The numbers in an algebraic expression take on different names according to its relationship with the variable:

• The numbers you are multiplying to the variable are the coefficients.
• Numbers that are not multiplying the variable are the independent terms.
• The powers to which the variable is elevated variable are the exponents.