Have you ever have been asked by your students, "what are matrices for?" If so, this case may help you show your skeptical students how important matrices are in real life.

This case put students in the shoes of Natalie, a recent IE University graduate. Natalie studied Math in her first year, but she never believed that matrices would be helpful in real life. One day, Natalie receives a mysterious (i.e., encrypted) message. She must discover the original message by using matrices.

In this case, students will have to work in groups to find an encrypted message given as a sequence of N numbers (where N is the number of characters and spaces required to write the message). The numbers shown in the case correspond to an encrypted message by using an unknown matrix A. Students must find A from the hints that a secret agent gives them during the case. Then, they must deduce that the inverse of matrix A will help them find the numbers representing the letters in the alphabetical order, 0 reserved for the spaces.

 The students usually find this case very challenging and exciting. It is an excellent way to show them the matrices’ applicability. Typically, students are completely lost at the beginning of the case; they focus on their studied concepts but rarely think out-of-the-box. There is a critical point when students discover how to use the four numbers for building the matrix A. A second cornerstone happens when they figure out that they need the inverse matrix to obtain the decoded numbers.