Solve+a+System+of+Equations+by+Elimination

Felipe Orestes, Alex Noonan

Summary -

Procedure -

1. Make sure that either the X or Y cancel out if not find a GCF for both and multiply ex: 2x+4y=7--> x -4 --> -8x-16y=-28 8x+4y=4 --> x1 --> 8x+4y=4

2. Then cancel out the X or Y to leave you with one variable ex: 12y=-24

3. Then divide the variable from both sides ex: 12y/12=-24/12 --> y=-2

4. Finally take the answer and substitute it in the place of X ex: 2(-2)+4y=7

5. Finally solve ex: 4+4y=7 -4 -4 4y/4=3/4 y=3/4

Videos:

http://www.pascack.k12.nj.us/cms/lib5/NJ01000238/Centricity/Domain/87/Elimination.mov

http://www.pascack.k12.nj.us/cms/lib5/NJ01000238/Centricity/Domain/87/New%20Project%202.mov

http://www.youtube.com/watch?v=JNSYI3f5ktc