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Algebra I

Algebra is the language through which we describe patterns. Think of it as a shorthand, of sorts. As opposed to having to do something over and over again, algebra gives you a simple way to express that repetitive process. It's also seen as a "gatekeeper" subject. Once you achieve an understanding of algebra, the higher-level math subjects become accessible to you. Without it, it's impossible to move forward. It's used by professionals of all kinds, not just college-bound ones. In these tutorials, we'll cover a lot of ground. Some of the topics include linear equations, linear inequalities, linear functions, systems of equations, factoring expressions, quadratic expressions, exponents, functions, and ratios.
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Multiplying and factoring expressions
This topic will add a ton of tools to your algebraic toolbox. You'll be able to multiply any expression and learn to factor a bunch a well. This will allow you to solve a broad array of problems in algebra.
All content in “Multiplying and factoring expressions”

Multiplying and dividing monomials

"Monomials" sounds like a fancy word, but it just refers to single terms like "4x" or "8xy" or "17x^2z". In this tutorial, we'll learn to multiply and divide them using ideas you're already familiar with (like exponent properties and greatest common factor).

Multiplying binomials

In this tutorial you'll learn that multiplying things like (4x-7)(-9x+5) just require the distributive property that you learned in elementary school. We'll touch on the FOIL method because it seems to be covered in a lot of schools, but we don't like it (we don't think it is good to memorize processes without knowing the why).

Factoring simple expressions

You already know a bit about multiplying expressions. We'll now reverse course and look at how to think about an expression as the product of simpler ones (just like we did when we find the factors of numbers).

Factoring quadratic expressions

Not only is factoring quadratic expressions (essentially second-degree polynomials) fun, but it is good for you. It will allow you to analyze and solve a whole range of equations. It will allow you to impress people at parties and move up the career ladder. How exciting!

Factoring by grouping

Factoring by grouping is probably the one thing that most people never really learn well. Your fate doesn't have to be the same. In this tutorial, you'll see how factoring by grouping can be used to factor a quadratic expression where the coefficient on the x^2 term is something other than 1?

Factoring quadratics in two variables

We'll now extend the application of our quadratic-factoring toolkit, by factoring expressions with two variables. As we'll see, this is really just an extension of what you probably already know (or at least will know after working through this tutorial). Onward!

Polynomial basics

"Polynomials" sound like a fancy word, but you just have to break down the root words. "Poly" means "many". So we're just talking about "many nomials" and everyone knows what a "nomial" is. Okay, most of us don't. Well, a polynomials has "many" terms. From understanding what a "term" is to basic simplification, addition and subtraction of polynomials, this tutorial will get you very familiar with the world of many "nomials." :)

Multiplying polynomials

You'll see in this tutorial that multiplying polynomials is just an extension of the same distributive property that you've already learned to multiply simpler expression (that's why we think FOIL is lame--it doesn't generalize and it is more memorization than real understanding).