You have not provided the coordinates, therefore, I can only help you with the concepts.
1- If the coordinates of C and D are given:
If the coordinates of C and D are given as:
C = (x₁,y₁)
D = (x₂,y₂)
We can simply get the slope using the following formula:
slope = [tex] \frac{ y_{2}- y_{1} }{ x_{2} - x_{1} } [/tex]
2- If the coordinates of A and B are given along with a relation between the two lines:
a- We will get the slope of AB using the formula above
b- If we are given that AB is parallel to CD, then:
slope of CD = slope of AB
c- If we are given that AB is perpendicular to CD, then:
slope of CD = 1 / (slope of AB)
Hope this helps :)
