Raymond B. answered 02/09/23
Math, microeconomics or criminal justice
for a point (a,c) and line y=mx +b
a parallel line through the point will have the equation
y-c = m(x-a) +b in point slope form
or
y = mx -ma +b+c
where m is the slope and b+c-ma = the y intercept
to take a specific example
y=2x + 2 has a parallel line through the point (0,3)
y = 2x +3
parallel lines have the same slope = the coefficient of the x term when the linear equation is solved for y
a perpendicular line has slope = negative inverse or -1/2 in this example or -1/m more generally where m = slope of the given line
y = -x/2 +3 is the perpendicular line through the point (0,3)