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kenneyfamily
4x - y = 1 x + 2y = 7 how could i solve this using an inverse matrix?
1) Use the coefficients to form a 2x2 matrix. 2) Augment this matric by I2 3) Perform row operations to find the inverse of the original matrix. Are we ringing bells?
would you write the matrix as 4 -1 1 2
That is part #1. Very good. Next...
what do you mean by augment it by I2?
\[\left[\begin{matrix}4 & -1 & 1 & 0\\ 1 & 2 & 0 & 1\end{matrix}\right]\]
why did you do that? sorry i'm confused
Well, this is one very useful way to find an Inverse Matrix. You've never seen it, before?
I may have but I forgot how to do it
How about "Elementary Row Operations"? Any of those floating around in your bag of tricks?
I wish I could say yes but no. I'm retaking a pre-calc course because i failed it the first time
Well, you're going to have to get a few things up to speed. Finding an inverse matrix is an important skill. You'll have to start somewhere. Try this: http://www.youtube.com/watch?v=RsTdy2r9DHk