Hello, Undefdisfigure!

We would find vector like this . . .Let: .

(a) Find point such that is a parallelogram where vertex is opposite

. .

Let

We know that: .

We would find vector CD like this:

. .

So we have: .

Therefore: .

(b) Write parametric equations and symmetric equations of the line

passing through and parallel to the segment

The direction of is: .

The line through with direction has equations:

. . . . . . and . .