I will give the BRAINIEST!!! Please help!!

The partial blueprint for an office building shows one outer wall and a perpendicular inner wall. Which of the following could be the equation of the inner wall, if the outer wall is represented by the equation y = 2/5x-1

a. y= -5/2x -4
b. y= -2/5x-4
c. y=5/2x-4
d. y=2/5x-4​