Problem 18:
Given a point $A$, a point $C$ and a point $M_{c}$, construct the triangle ABC.

Construction: 
1. Using the point $A$ and the point $M_{c}$, construct a point $B$ (rule W01);
2. Using the point $A$ and the point $B$, construct a point $\_M_{c}$ (rule W01);

Statement:
Prove that the point $M_{c}$ is identical to the point $\_M_{c}$.

