First we need to calculate lenght of each side of triangle.
we use formula for finding distance between 2 points in xy coordinate system.
AB = √13
BC = √13
AC = √26
In order for triangle to be equilateral it must have all 3 sides equal lenght which in this case isn't correct. In order for it to be right it has to suit pythagoras theorem.
AC^2 = AB^2 + BC^2
expressing values of AC, AB and BC we can see that condition for right triangle is fulfilled.
Answer is RIGHT.
