Chứng minh ΔAHM = ΔDCM

To prove that triangles ΔAHM and ΔDCM are congruent, we can use the Side-Angle-Side (SAS) congruence criterion. Here are the steps:

1. **Identify the Given Information:**
- Let \( A, B, C \) be points such that \( \angle A = \angle B = \angle C \).
- \( H \) is a point on line \( AB \) such that \( D \) divides \( AH \) in a certain ratio.
- \( M \) is a point on line \( AH \).

2. **Establish Corresponding Parts:**
- We have \( AM = MD \) (given),
- \( HM = HM \) (common side),
- \( \angle AHM = \angle DCM \) (assuming alternate interior angles or vertical angles based on line intersections).

3. **Apply the SAS Congruence Criterion:**
- Since two pairs of sides and the included angle are equal, we can conclude:
\[
ΔAHM ≅ ΔDCM
\]

This concludes the proof that the triangles are congruent.