Construct a 2 by 3 system that has these particular and homogeneous eq

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Homework Statement


Construct a 2 by 3 system Ax = b with particular solution xp = (2,4,0) and homogeneous solution xn = any multiple of (1,1,1).

The answer is {{1,0,-1},{0,1,-1}} x = {{2},{4}} which has xp and xnull = (c,c,c).

Homework Equations


Ax = b

The Attempt at a Solution


I tried putting (2,4,0) as row 1 and (1,1,1) as row 2 and then reducing, I get {{1,0,2},{0,1,-1}} but, that doesn't seem to match up with the answer.

Could someone please tell me how to do such a problem?

Any input would be greatly appreciated!
 
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Similar to solving those problems, it is useful to begin with the homogeneous solution. The particular solution can be added afterwards.

The answer is
One possible answer.
 
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