For lines to be perpendicular to each other their slopes must be negative reciprocals of one another, mathematically:
m1*m2=-1
Since y=2x-1 has a slope of 2, our perpendicular line must have a slope of:
2m=-1, m=-1/2, so our perpendicular line will be of the form:
y=-x/2+b, using the point (-2,-2) we can solve for the y-intercept, or "b".
-2=--2/2+b
-2=1+b
b=-3, then our perpendicular line is:
y=-x/2-3 or more neatly
y=-0.5x-3
