Solve a System of three variables when given one variable

The video tutorial explains how to solve a system of three equations by reducing it to two equations with two variables. The teacher demonstrates finding the value of Z, substituting it into the equations, and solving the resulting system using substitution. The process is recapped, highlighting the steps taken to find the values of X, Y, and Z.

Explain how the teacher solved for Y after substituting the value of Z.

Describe the process of substitution as used in the lesson.

What was the final outcome after solving the system of equations?