More Lessons: http://www.MathAndScience.com Twitter: https://twitter.com/JasonGibsonMath In this lesson, you will learn how to solve systems of equations that contain 3 variables. When a system has three variables, you must have three independent equations in order to solve the system. We first discuss what a system like this looks like in 3D space. Each equation represents a plane. The planes intersect in such a way as to produce one-solution, no-solution, or an infinite line of solutions. We discuss this along with the method to solve these systems by substituting variables.