Addition elimination method 1 | Systems of equations | 8th grade | Khan Academy | Summary and Q&A

308.4K views
March 10, 2011
by
Khan Academy
YouTube video player
Addition elimination method 1 | Systems of equations | 8th grade | Khan Academy

TL;DR

Learn how to solve a system of equations using the elimination method by adding the equations together to eliminate one variable.

Install to Summarize YouTube Videos and Get Transcripts

Questions & Answers

Q: What is the first step in solving this system of equations?

The first step is to choose an elimination method and add the equations together to eliminate one variable.

Q: How is the variable 'y' eliminated in this example?

By adding the equations together, the positive 2y and negative 2y terms cancel out, resulting in the elimination of 'y'.

Q: How do you determine the value of 'x'?

After eliminating 'y', the resulting equation is solved for 'x' by simplifying and isolating the 'x' variable.

Q: How do you find the value of 'y'?

Once 'x' is found, it can be substituted back into either of the original equations to solve for 'y' by simplifying and isolating the 'y' variable.

Summary & Key Takeaways

  • Two equations are given: x + 2y = 6 and 4x - 2y = 14.

  • The elimination method is used by adding the equations together to eliminate the variable 'y'.

  • The resulting equation is 5x = 20, solving for x.

  • Substituting x = 4 into one of the original equations gives y = 1.

  • The solution to the system of equations is x = 4 and y = 1, representing the point of intersection of the lines.

Share This Summary 📚

Summarize YouTube Videos and Get Video Transcripts with 1-Click

Download browser extensions on:

Explore More Summaries from Khan Academy 📚

Summarize YouTube Videos and Get Video Transcripts with 1-Click

Download browser extensions on: