Answer:
your awnser should be. 4 1/3 - 2 4/5 = 1 8/15
You have to shoe that the angles between adjacent sides = 90 degrees. You do do this by showing the adjacent sides are perpendicular by comparing their slopes.
The red lines mean the sides with the lines are the same. The red arc means those angles are the same.
Using that information you know the angle where the two same sides connect would also be the same.
So you have one side (S) and 2 angles (A) that are identical.
You can use B. ASA
