Introduction to Variables & Expressions

What is this "x" you're suddenly hearing about, and if it's a "variable" how can you "solve" for it? In this chapter we won't solve for x, but we will talk about the mundane day-to-day problems you'll have to do using it, including plugging values for it. I find the way students can get their head around x the easiest is to just stop trying to get their heads around it and just learn the steps for doing the problems. Then a few weeks later they'll get a good grade on a test and realize, "whoa, I think I get this x stuff!"

Intro to Variables & Expressions (free)

Let’s face it, the craziest thing about algebra is it’s the first time you see letters in math. X is the most famous of them, but we can use any other letter of the alphabet (and I often will to get you used to it). In this video, we’ll quickly talk about what variables and expressions are, then we’ll get some practice using them, and plugging numbers in for x to "evaluate" expressions.

Checking If A Number Is A Solution

Throughout Algebra you'll learn how to solve all kinds of different equations using all kinds of different strategies, but one step will always remain the same: checking your answer! To prepare you for that, in this video we won't solve anything; I'll just give solutions and we'll check to see if they're right. ("Why not just check the back of the book," you ask? While I advocate that for homework, it won't work on tests.)

How to Translate Words Into Equations

I've never met a student who liked word problems, and they only get worse the further you get into math. However, if you look at them like a foreign language, you just need a pocket translation dictionary to translate the words into symbols, and that's what this video is all about. Sum, difference, quotient, increased by, decreased by, product -- all these words translate directly into numbers and symbols, and this video shows you how.