Hi everyone!(adsbygoogle = window.adsbygoogle || []).push({});

I'm in need for some help with Matrix Reduction! I have two questions:

Question 1

Find the inverse of Matrix A by reducing the array (A|I), where

A=

2 4 6

4 5 5

3 1 -3

Question 2

Find all solutions of the following system:

2x_{1}+ 4x_{2}+ x_{3}- 3x_{4}- 3x_{5}= -5

x_{1}+ 2x_{2}- x_{3}+ 3x_{4}- 3x_{5}= -4

-2x_{3}+ 7x_{4}- x_{5}= 0

x_{1}+ 2x_{2}+ x_{4}- x_{5}= -1

The first two images are my attempt at question 1 - I get stuck and can't seem to get the identity matrix on the left. I know the answer (in red) through using a Matrix Calculator.

The last two images are my attempt at question two. I get stuck trying to find x_{2}and x_{1}using back substitution. Any suggestions?

*My apologies for the bad handwriting! Imgur is playing up and won't let me rotate the last 3 photos either :(

Image 1 - http://imgur.com/hXHhh

Image 2 - http://tinypic.com/view.php?pic=29kpg5l&s=7

Image 3 - http://tinypic.com/view.php?pic=9zrkex&s=7

Image 4 - http://tinypic.com/view.php?pic=33cxfuh&s=7

Thanks for any help in advanced!

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# Homework Help: Matrix Reduction

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