the direction and length of a straight line from from the starting point to the ending point of an object's motion

Question

and 1-29 or 1-19

Answer 1

If we are using 2D coordinates, then

d^2 = (x2-x1)^2 + (y2-y1)^2
tanθ = (y2-y1)/(x2-x1)

Now go for it, with a little thought of your own...