Addition elimination method 1  Systems of equations  8th grade  Khan Academy  Summary and Q&A
TL;DR
Learn how to solve a system of equations using the elimination method by adding the equations together to eliminate one variable.
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.