You work for an art store that has decided to carry every style and size of drafting triangle in existence. Unfortunately, sorting these has become a problem. The manager has given you the task of organizing them. You have decided to classify them by edge length and angles. To measure each triangle, you set it on a large sheet of very accurate graph paper and record the coordinate of each point. You then run these three points through a computer program to classify the triangles according to:
Scalene no equal sides
Isosceles two equal sides
Equilateral three equal sides
and
Acute all angles under 90
Right one angle equal 90
Obtuse one angle over 90
Of course, sometimes you make mistakes entering the data, so if you input points that do not form a valid triangle, your program should tell you.