If three distinct points $A, B,$ and $C$ in $a$ plane are such that the slopes of nomvertical line segments $A B, A C,$ and $B C$ are equal, then $A, B,$ and $C$ are collinear: Otherwise, they are not. Use this fact to determine whether the three points given are collinear.
$$
(-1,-3),(-5,12),(1,-11)
$$