First we will calculate the distance between all pairs of points from the given pairs. First consider the points (4, 0) and (-1, -1). The distance is given as follows: d1=√(42−(−1)2)+(02−(−1)2)=√17+1=3√2 Now consider the pair (-1, -1) and (3, 5). The distance is given as follows: d3=√(32−(4)2)+(52−(0)2) =√25+25 =5√2 Therefore, no distances are equal thus, the triangle is not isosceles. The greatest side is of length 5√2. We will square the remaining sides and add them up. (3√2)2+62=54 But (5√2)2=50. Therefore, by using inverse of the Pythagorean theorem, we conclude that the triangle is not right-angled either.