\[\boxed{\mathbf{414.еуроки - ответы\ на\ пятёрку}}\]
\[Дано:\]
\[AB = m \bullet E_{1}F_{1};\ \]
\[AB = n \bullet E_{2}F_{2};\]
\[E_{1}F_{1} = a \bullet E_{2}F_{2}.\]
\[Найти:\]
\[a - ?\]
\[Решение.\]
\[1)\ AB = m \bullet E_{1}F_{1}\ и\ AB =\]
\[= n \bullet E_{2}F_{2}:\]
\[\ m \bullet E_{1}F_{1} = n \bullet E_{2}F_{2}.\]
\[2)\ E_{1}F_{1} = \frac{n}{m} \bullet E_{2}F_{2}:\]
\[a = \frac{n}{m}.\]
\[Ответ:длина\ отрезка\ E_{1}F_{1}\ \]
\[выражается\ числом\ \frac{n}{m}\text{.\ }\]