Need Math Help. I want to ask questions about math problems that i don't understood. For example, Equations, Distribute numbers, and Simplify Expressions.

3x means you have three x's. Then 3x - x means you have three x's and you take away (subtract) one x. This would leave you with two x's. But we write that as 2x - that is, two x's. Therefore,

3x - x = 2x