# 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.

## Introduction to algebra

Videos exploring why algebra was developed and how it helps us explain our world.

## Linear equations

We will now equate two algebraic expressions and think about how it might constrain what value the variables can take on. The algebraic manipulation you learn here really is the heart of algebra.

## Linear inequalities

Exploring a world where both sides aren't equal anymore!

## Two-variable linear equations and introduction to functions

Learn all about linear equations and their graphs. Model real-world situations by writing linear equations and functions.

## Functions

Functions are mathematical entities that assign unique outputs to given inputs. Sounds simple? Think again!
In this topic you will evaluate, graph, analyze, and create various types of functions.

## Sequences

You may have worked with patterns in earlier grades, now it's time to move on to sequences! Did you know sequences are simply functions, defined over the whole numbers?
In this topic you will learn about the explicit and the recursive definitions of sequences, and about arithmetic and geometric sequences. You will evaluate sequences, construct sequences, and model real-world situations with sequences.

## Systems of linear equations

Learn how to interpret solutions to systems of linear equations and solve them.

## Two-variable linear inequalities

In these tutorials, we study inequalities like x+2y>5 and graph them. This helps us see their solutions. We also explore systems of inequalities (multiple inequalities at the same time) and use them to describe real-world situations.

## Introduction to polynomials and quadratic factorization

Learn how to add, subtract, multiply, and factor polynomial expressions.

## Quadratic equations

In this topic, we'll analyze, graph and solve quadratic equations.

## Expressions with rational exponents and radicals

Learn about expressions with rational exponents like x^(2/3), about radical expressions like √(2t^5), and about the relationship between these two forms of representation. Learn how to evaluate and simplify such expression.

## Rational and irrational numbers

Learn about irrational numbers and how to identify them.