รบกวรช่วยแก้โจทย์นี้ให้หน่อยครับ ม.5 เรขาคณิต

Given that the circumcenter of acute triangle ABC is D,the circle passing through A,B,D intersects AC and BC at M and N respectively.Prove that the radius of the circumcircle of MNC is equal to the radius of the circumcircle of ABD