The shaded area is everything GREATER than but not including the line (because it is dashed)
Find slope of the line using two convenient integer points slope = rise / run = 2
b, the y axis intercept is shown to be +1
so the line equation is y = 2x+1
the shaded area is y > 2x+1 re-arrange to the requsted form
-2x+y -1 > 0