725.
$%{x^4} - 22{x^2} - 5x + 2 = 0$%
726.
$%{x^4} - 7{x^2} - 2x + 17 = 0$%
1718.
\[\begin{array}{l}
{\text{Решите систему уравнений:}} \hfill \\
\left\{ \begin{array}{l}
{a^2} + bc = 7 \hfill \\
ab + bd = 3 \hfill \\
ac + dc = 2 \hfill \\
bc + {d^2} = 6 \hfill \\
\end{array} \right. \hfill \\
\end{array}\]