Have you ever wanted to send encrypted messages but didn't know how?! Well, this video is going to show you how using the wonders of matrices. This video is another in the matrices series for the Units 1 and 2 General Maths series (VCE). I take a look at how we can use matrix multiplication to send encoded messages using a simple cypher and the mathematics we have been looking at before. This video builds on the previous video where we looked at the Identity and Inverse matrices and shows how we can use them (with the CAS) to encode and decode messages. Let the spy school training begin!