# 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 people with lots of different jobs, like carpentry, engineering, and fashion design. 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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# Systems of equations and inequalities

Solving a system of equations or inequalities in two variables by elimination, substitution, and graphing.
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All content in “Systems of equations and inequalities”

## Introduction to systems of linear equations

Introduction to systems of linear equations

## Graphical representation of systems of equations

Graphing a system of equations turns out to be a VERY effective way of analyzing and solving them. Let's try it!

## Equivalent systems of equations and the elimination method

We already know how to manipulate a single equation to obtain equivalent forms of it. Let's learn how to manipulate entire systems in order to solve them algebraically.

## Solving systems of equations with substitution

More ways to manipulate systems of equations in order to solve them

## Analyzing the solutions to systems of equations

A single linear equation usually has a single solution, but it may have zero or infinite solutions. It turns out that the same goes for systems of equations! Let's learn how that happens.

## Systems of linear equations word problems

Now that we are able to solve any kind of system we are given, it's time to use that knowledge to solve some word problems.

## Graphing linear inequalities

In this tutorial we'll see how to graph linear inequalities on the coordinate plane. We'll also learn how to determine if a particular point is a solution of an inequality.

## Systems of inequalities

You feel comfortable with systems of equations, but you begin to realize that the world is not always fair. Not everything is equal! In this short tutorial, we will explore systems of inequalities. We'll graph them. We'll think about whether a point satisfies them. We'll even give you as much practice as you need. All for 3 easy installments of... just kidding, it's free (although the knowledge obtained in priceless). A good deal if we say so ourselves!

## Modeling constraints

In this tutorial, we'll use what we know about equations, inequalities and systems to answer some very practical real-world problems (and a few fake, impractical ones as well just for fun).