Linear algebra: augmented matrix of a consistent system

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Homework Statement



Determine the values of h such that the matrix is the augmented matrix of a consistent linear system.
[1 h -5]
[2 -8 6]


Homework Equations




None that I know of.

The Attempt at a Solution



Multiplied row (1) by -2:
[-2 -2h 10 ]
[ 2 -8 6 ]

and added together to get: -2h -8 = 16
and of course you can solve that for -2h=24
and h = -12.

So is it correct to say H can be any value other than -12 in order to make the system consistent? Please let me know if its correct. If not, please tell me what I need to do to get the correct answer. Thanks!
 
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[-2 -2h 10 ]
[ 2 -8 6 ]

If you add together row 1 and 2 you will get

[-2 -2h 10]
[0 (-2h-8) 16]

so yes -2h-8= 16 is one equation but will your matrix still be consistent if -2h-8 = 0?
 
Also, remember the matrix consists of only the coefficients of the equations. That second line corresponds to the equation (-2h-8)y = 16.

What does it mean when a system is said to be consistent? How can that idea be related to that second equation?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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