Find a solution to a junior high school math problem. The topic is selected from Question 18 of the second set of model mathematics test paper for grade 9 in Heping District, Tianjin in the 2022-2023 school year. Hello, the question you asked is a simple junior high school math problem.

This problem mainly investigates the calculation of geometric figures.

The solution to this problem is

According to the question, the angle is equal to 90 degrees.

And AM=AN

Then the triangle is an isosceles right triangle.

When determining the positions of m and n

First, draw the diameter of point A.

Then draw a diameter perpendicular to the diameter of A at the center of the circle.

The intersection of diameter and circle is m, n.

I hope it will be helpful to you and I hope it will be adopted.