Answer: The lines L1 and L2 are parallel.
Step-by-step explanation: We are given to determine whether the following lines L1 and L2 passing through the pair of points are parallel, perpendicular or neither :
L1 : (–5, –5), (4, 6),
L2 : (–9, 8), (–18, –3).
We know that a pair of lines are
(i) PARALLEL if the slopes of both the lines are equal.
(II) PERPENDICULAR if the product of the slopes of the lines is -1.
The SLOPE of a straight line passing through the points (a, b) and (c, d) is given by
So, the slope of line L1 is
and
the slope of line L2 is
Therefore, we get
Hence, the lines L1 and L2 are parallel.