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Thinking about solving equations

6 videos
1 skill
Much of algebra seems obsessed with "doing the same thing to both sides". Why is this? How can we develop an intuition for which algebraic operations are valid and which ones aren't? This tutorial takes a high-level, conceptual walk-through of what an equation represents and why we do the same thing to both sides of it. Common Core Standard: 6.EE.B.7

Why we do the same thing to both sides: Simple equations

VIDEO 2:32 minutes
The example of a scale where we try to achieve balance helps to explain why we do the same thing to both sides of an equation.

Representing a relationship with a simple equation

VIDEO 3:24 minutes
Equations are about relationships (no, not girlfriends and boyfriends!) between the two sides of the equation. Let's again use a scale example to help us understand.

One-step equation intuition

VIDEO 4:39 minutes
This equation can be simplified through a single step to solve for the variable. Can you help?

One step equation intuition introduction

VIDEO 1:51 minutes
To find the value of a variable, you sometimes have to get it on one side of the equation alone. To do that, you'll need to do something to BOTH sides of the equation. Watch. We'll explain why we do this.

One step equation intuition

PRACTICE PROBLEMS
Explore why we do the same things to both sides of an equation

Adding and subtracting from both sides of an equation

VIDEO 2:09 minutes
Let's watch as we demonstrate how we add and subtract to both sides of an equation in order to isolate the variable on one side.

Dividing from both sides of an equation

VIDEO 3:14 minutes
Let's get a conceptual understanding of why one needs to divide both sides of an equation to solve for a variable.