If a line is perpendicular to other his slopes are the opposite inverse of each other
So, if y = -2x - 4 we have the slope of -2, so the slope of the other line will be the opposite inverse which means
opposite of -2 = 2
inverse of 2 = 1/2
So our slope is 1/2
(y - yo) = m.(x - xo)
(y - 4) = 1/2.(x - 3)
y - 4 = x/2 - 3/2
y = x/2 - 3/2 + 4
y = x/2 + 5/2
