Pre-algebra

No way, this isn't your run of the mill arithmetic. This is Pre-algebra. You're about to play with the professionals. Think of pre-algebra as a runway. You're the airplane and algebra is your sunny vacation destination. Without the runway you're not going anywhere. Seriously, the foundation for all higher mathematics is laid with many of the concepts that we will introduce to you here: negative numbers, absolute value, factors, multiples, decimals, and fractions to name a few. So buckle up and move your seat into the upright position. We're about to take off!
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Negative numbers and absolute value

Factors and multiples

Understanding and finding factors and multiples. After these videos, you'll be ready for fractions.

Decimals

Fractions

Ratios, proportions, units, and rates

Applying mathematical reasoning

You already have many tools in your mathematical toolkit. In this topic, you'll use these in settings that you're likely to encounter in the real world!

Exponents, radicals, and scientific notation

Understanding and solving exponents without algebra.

Arithmetic properties

This tutorial will help us make sure we can go deep on arithmetic. We'll explore various ways to represent whole numbers, place value, order of operations, rounding and various other properties of arithmetic.

Measurement

From length to area to volume to time, thinking about how we measure things.

Negative numbers and absolute value

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All content in “Negative numbers and absolute value”

Negative number basics

What is a "negative number"? What happens when I add or subtract one of these? If you come to this tutorial armed with the basics of adding and subtracting numbers, you'll learn about what happens in the world below zero! You will learn what negative numbers are and how we can add and subtract them.

Adding and subtracting negative numbers

You understand that negative numbers represent how far we are "below zero". Now you are ready to add and subtract them! In this tutorial, we will explain, give examples, and give practice adding and subtracting negative numbers. This is a super-important concept for the rest of your mathematical career so, no pressure, learn it as well as you can!

Multiplying and dividing negative numbers

It is starting to dawn on you that negative numbers are incredibly awesome. So awesome that you are feeling embarrassed to think how excited you are about them! Well, the journey is just beginning. In this tutorial we will think about multiplying and dividing numbers throughout the number line!

Absolute value

You'll find absolute value absolutely straightforward--it is just the "distance from zero." If you have a positive number, it is its own absolute value. If you have a negative number, just make it positive to get the absolute value. As you'll see as you develop mathematically, this idea will eventually extend to more contexts and dimensions, so it's super important that you understand this core concept now.