Question 108833
For points to be collinear, the change in y divided by the change in x is constant and equal to the slope of the line connecting the two points. 
The slope between A and B is zero, since the change in y is zero (1-1=0).
The slope between A and C is not zero, since the change in y is not zero (-3-1=-4). 
Therefore the points are not collinear. 
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