Answer:
y =
x - 1
Step-by-step explanation:
the equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y-intercept )
y = -
x - 3 is in this form
with slope m = - 
the slope of a perpendicular line is the negative reciprocal of m, hence
= 
(0 , - 1 ) is the y-intercept ⇒ c = - 1
y =
x - 1 ← equation of perpendicular line