I need help with this! I am struggling and don’t know what to do for this question. I need a answer may someone please help me? It would be very very Helpful!

∞ this is your sign

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.