\[\boxed{\ \mathbf{73}\mathbf{\ (67)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]
\[MT = FK\]
\[MT = MF + FT\]
\[FK = FT + TK \Longrightarrow\]
\[\Longrightarrow MF + FT = FT + TK;\ \ то\ \]
\[есть\ MF = TK.\]