\[\boxed{\mathbf{646\ (646).\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[x^{2} + 5x - 1 + \ *\ = 0\]
\[Пусть\ y = \ *\ .\]
\[1)\ Если\ x = 0\ \ \ и\ \ x = - 7,\ \ \ \]
\[запишем:\ \]
\[x(x + 7) = 0\]
\[x^{2} + 7x = 0\ \ \ \ \ \ и\ \ \ \ \ \ \]
\[x^{2} + 5x - 1 + \ *\ = 0\]
\[\left( x^{2} + 5x - 1 \right) + \underset{y}{\overset{2x + 1}{︸}} = 0\]
\[y = 2x + 1.\]
\[2)\ Если\ x = - 4\ \ \ и\ \ x = 4,\ \ \ \]
\[запишем:\]
\[(x + 4)(x - 4) = 0\]
\[x^{2} - 16 = 0\ \ \ \ \ и\ \ \ \ \ \ \]
\[x^{2} + 5x - 1 + \ * = 0\]
\[\left( x^{2} + 5x - 1 \right)\underset{y}{\overset{- 5x - 15}{︸}} = 0\]
\[y = - 5x - 15.\]