Question 769836
y=2x-1

compare with y=mx+b

m=2 slope

perpendicular line will havea slope of -1/2

and passes through (2,-2)

use the slope point formula 
y-y1= m(x-x1)

y-(-2)=-(1/2)(x-2)

y+2=-1/2x +1
y=(-1/2)x -1 is the equation