Answer:
1. y ax
|
A-------------------------------B
|
------------C---------------------
|
|__________________x ax
for this, your A might be (0,5), B (5,5), C (2,2).
parallel means railroad tracks: same slope, different intercepts.
line AB in this case has a slope of 0, intercept (0,5), so y₁=0x+5 or just y₁=5
the line passing through C also has slope 0, but intercept (0,2), so y₂=0x+2 or just y₂=2
2. perpendicular means that the slopes of two lines multiply out to -1. If line AB has, for example, a slope of 2/3, then the line passing through C would have slope -3/2 (negative reciprocal). To make things easier have either point A or B be on the x or y axis
khan academy has some helpful videos :)
https://www.khanacademy.org/math/geometry/hs-geo-analytic-geometry/hs-geo-parallel-perpendicular-eq/v/perpendicular-lines
