# Thread: Tangency of circles - proof

1. ## Tangency of circles - proof

Hi!

Could you help me solve the following problem?

In a convex quadrangle ABCD we have: $< DAB + 2 < BCD = 180^o$

The circle inscribed in the triangle ABD i tangent to the sides AB i AD in the points M and N respectively. Prove that the circles circumscribed around triangles AMN and BCD are tangent.

Thank you

2. ## Re: Tangency of circles - proof

Have you drawn a sketch of the problem?
Where exactly are you stuck?