Matrix and Vectors ?

Question

A = 2 1.............b = 3

......4 3...................4

Given the matrix A and vector b and an unknown vector x

such that x = x1

....................x2

expand as a set of equations and solve them to find x

Extra info:

The x1 and x2 actually have x with a small number to the bottom right corner of the x, like a power but bottom right not top right. The dots are just for spacing. I hope its understandable.

PLEASE show the method, if your unable to show the method (which seems to be a common trend with this question) then don't bother, if i just wanted the answer i would use a calculator >.< Thank you

Answer 1

I sometimes wonder what yahoo does with my solutions...worked this problem for someone who had the x2 solution but it is not in my set. Anyway you look at the &quot;augmented&quot; matrix and do Gauss elimination...1st row is&lt; 2  1   3 &gt; and 2nd is &lt; 4  3  4 &gt;. So multiply row 1 by -2 and add to 2nd row to get a &#039;new &#039; 2nd &lt; 0  1  -2&gt;..this means x2 = -2 and the 1st row is  2 x1 + x2 = 3---&gt; x1 = [ 3 -(-2) ] / 2 = 5/2. Finished