Mathematics for grade 8
Welcome! I'm excited to help you conquer 8th-grade math and set you up for absolute success in high school algebra. Before we dive into the fun stuff, I want to make sure this is perfectly tailored to your goals.
To help me plan our pace, could you let me know if there's a specific area of math you're finding challenging right now, or are you looking for a general review of the 8th-grade curriculum?
Just need to brush up on the real number system first
Introduction to the Real Number System
Let's start our journey by looking at the numbers we use every single day. The universe of numbers is collectively known as the real number system, and we can split almost every number we encounter into two major, competing families: rational numbers and irrational numbers.
To make sense of this, let's think of rational numbers as the "friendly, predictable" family. Any is a number that you can write as a clean, simple fraction of two integers, like (where is not zero). Because they can be written as fractions, their decimal forms are highly predictable: they either stop completely (like ) or they repeat a pattern forever (like ).
Irrational numbers, on the other hand, are the "wild, infinite" family. They absolutely refuse to be written as simple fractions, and their decimals go on forever without ever repeating a clean pattern.
A Venn diagram showing the hierarchy of the real number system with nested and disjoint sets containing specific mathematical values.
See how those two groups are completely separated? A number can never be both rational and irrational at the same time; it has to pick a side! Now that we have seen the layout of this number map, let's explore how we can spot an irrational number just by looking at its decimal.