The given equation is in the point-slope form. The slope can be obtained by simple identification of the parts of the equation. This is shown below:
Given equation:
(y - 3) = -2 (x - 4)
y - y1 = m(x - x1)
Where slope, m = -2
The slope of a line perpendicular to the line CD is the negative reciprocal of the slope of the line CD. Therefore:
Slope = 1/2