75.522, 75.522, and 28.955. The smallest angle goes at the peak of the two longest lines. Like having 2 equal and one different line in an isosceles triangle, the angles follow suit. The angle size really depends on the length of the lines- the longer the lines, the smaller the angle (usually).
I would show you the math to get these, but I'm on an old computer and it's a pain to try to do lots of spaces instead of a tab....lol