Answer:
The triangle with vertices A (2 , 0) , B (3 , 2) , C (5 , 1) is isosceles right Δ
The triangle with vertices A (-3 , 1) , B (-3 , 4) , C (-1 , 1) is right Δ
The triangle with vertices A (-5 , 2) , B (-4 , 4) , C (-2 , 2) is acute scalene Δ
The triangle with vertices A (-4 , 2) , B (-2 , 4) , C (-1 , 4) is obtuse scalene Δ