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Getting a feel for equations and inequalities

8 videos
2 skills
The core underlying concepts in algebra are variables, expressions, equations and inequalities. You will see them throughout your math life (and even life after school). This tutorial won't give you all the tools that you'll later learn to analyze and interpret these ideas, but it'll get you started thinking about them.

Variables, expressions, and equations

VIDEO 6:55 minutes
This video will give you a great understanding of variables, expressions, and equations. If you've struggled with them before, this one may just do the trick!

Substituting variables and judging inequalities

VIDEO 4:47 minutes
In this word problem we're looking to see if various possible answers can be substituted for variables in the expressions, and if the resulting equality holds up. That may actually sound harder than it is, so just jump in with us!

Substituting variables and simple equation

VIDEO 1:16 minutes
This basic equation asks us to substitute for a variable with given values in order to find correct one.

Substituting variables and solving for an equality

VIDEO 2:24 minutes
The great thing about understanding expressions and equalities is that they can be used to solve real life problems, like how many dogs you can eat in a minute!

Substituting variables and solving for an inequality

VIDEO 2:33 minutes
Here's a slightly more complicated expression that seeks not equality, but a greater than relationship. Help us try out different values until we succeed.

Dependent and independent variables exercise: the basics

VIDEO 2:10 minutes
Here we have a problem that asks us to identify which variables are dependent and independent. Hint: independent variables are not influenced and remain unchanged by the other variable.

Dependent and independent variables exercise: graphing the equation

VIDEO 1:00 minutes
It's helpful to express an equation on a graph where we plot at least 2 points. Watch and we'll show you.

Dependent and independent variables exercise: express the graph as an equation

VIDEO 2:00 minutes
We're flipping the last video on its head and doing the opposite. This time we give you the graph and ask you to express it as an equation.