Trolls, kings, and solving systems of equations

2012-10-31 18:37:00 GMT

Sal has created new algebra videos to explain solving systems of equations:

Trolls, Tolls, and Systems of Equations

Then check out the follow-up videos on Solving the Troll Riddle Visually and Solving Systems Graphically.


The King’s planning a party and needs your help figuring out how many cupcakes to order.

King’s Cupcakes: Solving Systems by Elimination

This video leads into the first exercise on elimination, which has a new guide video: Simple Elimination Practice.

Then, the King needs more party planning help in managing The Potato Chip Issue:

How many bags of potato chips do people eat?

This leads into the next exercise on elimination, which also has a new companion video.


Next, a little bird visits the King to teach him a new solving method: substitution.

Talking bird solves systems with substitution

The exercise using substitution has a new companion video.

Solutions to Systems

Sal then investigates special situations you may run into, including systems without a solution:

Inconsistent systems of equations

and systems with infinite solutions:

Infinite solutions to systems

Our exercise on how many solutions a system of equations has also comes with a new companion video.