A line contains the points (1,-3) and (1, -2). Another line graphed in the same coordinate plane contains the points (-2,0) and (-3,-3).
Based on the slope of these lines, are they parallel, perpendicular or neither?

Question

A line contains the points (1,-3) and (1, -2). Another line graphed in the same coordinate plane contains the points (-2,0) and (-3,-3). 
Based on the slope of these lines, are they parallel, perpendicular or neither?

anonymous · Answer

using the slope formula: $$(y _{2} - y _{1})/ (x _{2} - x _{1})$$
you can find the slopes of the two lines.
L1 = (-2 - (-3))/(1 - 1) so the slope is undefined because you can't divide by zero.
L2 = (-3 - 0)/(-3 - (-2)) so the slope is (-3)/(-1) or just 3
the answer is neither.