If a = (8, 2) b = (11, 13) and c = (2, 6), classify the the following triangle as either right or isosceles

First we calculate lengths of each side of triangle.

AB = √((8-11)^2+(2-13)^2) = √130

BC =  √(81+49) = √130

CA = √52

Since we have 2 equal lenghts and the lenght of third one is smaller than lenght of first 2 that means that triangle cannot be right and is in fact isosceles. Other way to test that to check for pythagoras theorem.

Answer is Isosceles.