where D1 is the second intersection point of DP and γ. So m swaps B and C; hence, being a direct similitude, m is the reflection in the midpoint M of BC. It follows that the line DP = DD1 passes through M.
where D1 is the second intersection point of DP and γ. So m swaps B and C;hence, being a direct similitude, m is the reflection in the midpoint M of BC. Itfollows that the line DP = DD1 passes through M.