What 58x 55 what is the answer

The center of the circumscribed circle lies on line segment and the longest side of the triangle is equal to the of the circle.

At the beginning of 1974/75,2 years a man invested #2000 in a bank at 12.5% compound interest, if it degree #650 at the end of each two years to pay his son's school fees, after payment of interest to pay his son's school fees, how much did he have left at the beginning of the 1978/79 school year?

Which best explains why this triangle is or is not a right triangle ?