Let (`) be the line on R2 that passes thru 2 points P (−1, 2) and Q(1, 6).
(a) Find a direction vector and a normal vector of (`).
(b) Write equations of (`) in general, normal, parametric, and vector forms.
(c) Let A(11, 5) be a point outside that line. Find the distance from A to
the line (`).