Sign In | Subscribe

Enter your Sign on user name and password.

Forgot password?
  • Follow us on:
Start learning today, and be successful in your academic & professional career. Start Today!
Loading video...
This is a quick preview of the lesson. For full access, please Log In or Sign up.
For more information, please see full course syllabus of GRE/ACT/PSAT Math
  • Discussion

  • Download Lecture Slides

  • Table of Contents

  • Related Books & Services

Start Learning Now

Our free lessons will get you started (Adobe Flash® required).
Get immediate access to our entire library.

Sign up for

Membership Overview

  • Unlimited access to our entire library of courses.
  • Search and jump to exactly what you want to learn.
  • *Ask questions and get answers from the community and our teachers!
  • Practice questions with step-by-step solutions.
  • Download lesson files for programming and software training practice.
  • Track your course viewing progress.
  • Download lecture slides for taking notes.
  • Learn at your own pace... anytime, anywhere!

Systems of Equations

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

  • Intro 0:00
  • The Basics: Systems of Equations 0:19
    • Equations with Infinite Solutions
    • Number of Equations Should Match the Number of Unknowns
  • Why Manipulation and Combination is Often the Best Method 4:34
  • Why Addition and Subtraction of Equations is Valid 7:23
  • The Most Important Step--The Common Coefficient 10:41
  • Manipulation and Combination: Steps 13:50
  • Substitution 15:49
  • Which Method Should Be Used? 20:13
  • How to Solve Problems with Three Equations and Three Unkowns 22:58
  • Three Equation Example 24:22