Given the function $\displaystyle {n}{\left({x}\right)}={\left\lbrace\begin{array}{cc} {2}{x}-{9}&{x}\le-{1}\\{5}{x}^{{2}}+{7}{x}+{3}&{x}>-{1}\end{array}\right.}$
Calculate the following values:

$\displaystyle {n}{\left({1}\right)}=$
$\displaystyle {n}{\left(-{1}\right)}=$
$\displaystyle {n}{\left(-{6}\right)}=$
$\displaystyle {n}{\left(-{9}\right)}=$