I can't seem to find what method I should use to solve this right triangle.

I'll call the triangle ABC, with B being the 90 degree angle. Neither angle A or C are known. Side BC is 8 long, side AB is unknown.

A line segment goes from angle B to a point on AC, forming a 90 degree angle with it. From where this line segment meets AC down to angle A is 15 long.

Also, angles A and C are equal.