Answer:
Perpendicular.
Step-by-step explanation:
Find the slopes of each line through
Line a:
m = (-10-4) / (8--4)
= -14/12
= -7/6
Line b:
m = (20-8) / (18 -4)
= 12/14
= 6/7
When lines are parallel, they have the same slope. Since -7/2≠6/7, they are not parallel.
When lines are perpendicular, the product of the slopes equals -1.
-7/6 x 6/7 = -1
The product is -1, hence they are perpendicular lines.