Its finals I have 2 questions in one, so double points!

Todd IS doing something wrong, but what?

AND I need help on this one pls.

(click between the first and second pics, the 1st pic is for th 1st question, while the 2nd is for the 2nd)

wedfghjkl;

tyuiop[]ghjkl;

step-by-step explanatio89

9x

step-by-step explanation:

points a and b are equidistant from the desired line, so the line you find by using them will go through point r.

using points other than a and b will give the desired line only if they are equidistant from r. if they are randomly located, the perpendicular line you create will not necessarily go through point r, hence will not be a solution to the problem.