# Creating Expressions, Equations, and Inequalities

One of the most critical skills in algebra is learning to write an equation.  Being able to translate a problem -- whether a word problem or a real life problem -- into an equation opens up an entire realm of math.

So, how do you translate words into an equation?

First, some basics:

• Expressions, equations, and inequalities contain numbers. If you are given a relevant number, figure out how it fits into the equation.
• Numbers are often unknown. These unknown numbers should be represented by variables. Variables can be any letter. We often use x and n, but any letters will do. Generally, stay away from variables that look like numbers (e.g., l and g). If you are using several variables, it's good to have letters that are distinct (c and r can get confusing). If you are doing a word problem, it sometimes helps to use letters that represent items (e.g., if the farmer has more wheat then corn, then $w>c$ makes sense).
• Several words signal that you need to insert a variable: