Question 56646
For each of the following choices of A and b, determine if b is in the column space of A and state whether the system Ax=b is consistent. 
A=[1 2] b=[4]
[2 4] [8] 
CHECK THE RATIOS OF ELEMENTS IN THE 2 ROWS UNDER RESPECTIVE COLUMNS ARE EQUAL OR NOT...WE HAVE 
1/2,2/4,4/8....ALL ARE EQUAL TO 1/2 .SO THE SYSTEM AX=B IS CONSISTENT

also 
A=[1 1 2] b=[1]
[1 1 2] [2]
[1 1 2] [3]
WE HAVE
1/1,1/1,2/2,1/2....THEY ARE NOT ALL EQUAL.
1/1,1/2,2/2,1/3....THEY ARE NOT ALL EQUAL.
HENCE THE SYSTEM AX=B IS INCONSISTENT