# Equations, expressions, and inequalities

Contents

In this topic, we will look at 1- and 2-step equations, as well as expressions and inequalities.

See how you score on these 20 practice questions

Wait, why are we using letters in math? How can an 'x' represent a number? What number is it? This tutorial is great if you're just beginning to delve into the world of variables and expressions.

Learn how to substitute (or "plug in") values for variables and evaluate algebraic expressions.

Explore how the value of an algebraic expression changes as the value of its variable changes.

Let's construct and interpret expressions from word problems. We can also think about what the effects of parentheses are.

Learn how to plug in values to evaluate real-world expressions.

Learn the basics of writing expressions with variables.

Learn how to write algebraic expressions (expressions with variables) to model real-world situations.

Explore what it means for equations with variables (algebraic equations) to be solved.

A high-level, conceptual walk-through of what an equation represents and why we do the same thing to both sides of it

Solve equations by adding and subtracting numbers from both sides.

Solve equations by multiplying and dividing numbers from both sides.

Let's use our algebra tools to solve a problem of earth-shattering importance: which Super Yoga plan is the best value! In this word problem, you'll put to practice your knowledge of variables, substitution, and one-step equations.

Equality is usually a good thing, but the world is not a perfect place. No matter how hard we try, we can't help but compare one thing to another and realize how unequal they may be.
This tutorial gives you the tools to do these comparisons in the mathematical world (which we call inequalities). You'll become familiar with the "greater than" and "less than symbols" and learn to use them.

Learn how to solve equations like 2x+7=13 and 3(x+4)=3, which can be solved in two steps.