What is the area of the shaded region?
I'm honestly not at all sure about this but I think it's 2/3 of the area of the whole triangle, which should be 100/3.
Find the longest side of a shaded triangle using the Pythagorean theorem.
Use the trig to find angels of a shaded triangle.
.....hmmmmm..... not a right triangle....will not work....Pythag does not apply.....dang-o....