Consider the following points:

M (-6, 6) N (6, 4) O (-6, -4) P (8, -8)

Which of the following is true of lines MP and NO ?

Lines MP and NO are not parallel.

M (-6, 6) N (6, 4) O (-6, -4) P (8, -8)

Which of the following is true of lines MP and NO ?
find slope for MP
m = (-8-6) / (8+6) = -14/14 = -1
find slope for NO
m = (-4-4) / (-6-6) = -8/-12 = 2/3
so they are not perpendicular or parallel

Correct, lines MP and NO are not parallel or perpendicular.