System of 3 Equations

Sick of ads?​ Sign up for MathVids Premium
Taught by mrbrianmclogan
  • Currently 4.0/5 Stars.
5925 views | 1 rating
Part of video series
Meets NCTM Standards:
Lesson Summary:

In this lesson, viewers learn how to solve a system of equations using three variables. First, they need to identify the easiest variable to eliminate, which is often the one with the same coefficients in different equations. They then use elimination method to get rid of the variable and create a new equation. After eliminating twice, they will have two new equations with two variables to solve for, which they can either use elimination or substitution method. Finally, by plugging in one of the variables to the original equation, they can solve for the other two variables.

Lesson Description:

How to solve a system of equations with three variables

I show how to solve math problems online during live instruction in class. This is my way of providing free tutoring for the students in my class and for students anywhere in the world. Every video is a short clip that shows exactly how to solve math problems step by step. The problems are done in real time and in front of a regular classroom. These videos are intended to help you learn how to solve math problems, review how to solve a math problems, study for a test, or finish your homework. I post all of my videos on YouTube, but if you are looking for other ways to interact with me and my videos you can follow me on the following pages through My Blog, Twitter, or Facebook.

Questions answered by this video:
  • How would you choose which variable to eliminate first?
  • what should you do with the new equation you formed after the first elimination?
  • After forming one equation with 2 variables what should your next step be?
  • What options do you have when solving simultaneous equations in 2 variables?
  • Having found the value of 2 variables, what should your next step be ?