Mar 26, 2013

System of Equations (elimination)

I don't know about you but I really suck at the whole elimination part of this quarter so here is how to do it for those who are wondering

The idea of this whole thing is to get the equation so that there is only one variable.  How we do that in this method is by making the variables that you want to eliminate opposites so that they cancel each other out.  Remember that an equation stays the same if you add equal amounts to each side. Say you have the problem:
 x - 2y= -19
5x + 2y= 1       -2y and 2y cancel each other out when you add them together and then you just continue to add the rest of the equation   
   x = -19
+ 5x = 1
   6x = -18   then you just simplify 6x = -18   and you get   x = -3  ta da
                                                       6       6

sorry if my directions weren't that clear but it is page 343 in the text book

1 comment:

  1. Ah! This is actually so helpful! I had forgotten how to do this and on one problem just added them up as is. So I was combining -6x and 5x instead of converting the problem. Sorry that doesn't make sense.

    So helpful! Thank you!

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