Pleas help me with this exercises(this is not a homework):
Determine whether the points lie on a straight line.
a) A(5,1,3), B(7,9,-1), C(1,-15,11)
b) K(0,3,-4) L(1,2,-2), M(3,0,1)
Should I draw the graph, then find the slopes?
Or is there any other way to approach?
Pleas help...