Do you have any information about length of the sides maybe? By the way you do have information about at least one angle and it's 90 degrees (because triangle is a right one)
If there are no degrees indicated on the right triangle, it is not possible to determine the measure of any angle without additional information. In geometry, the measure of an angle is typically expressed in degrees. Without any degrees provided, it is impossible to calculate the exact measure of any angle in the triangle. Therefore, the claim that the measure of angle A, B, or C is 15 degrees without further information is incorrect.
