$$\left. \begin{array} { l } { ( y + 5 ) ( y + 5 ) } \\ { ( 9 m - \frac { 1 } { 2 } n ) ( 9 m - \frac { 1 } { 2 } n ) } \\ { ( 1.5 z - 0.6 ) ( 1.5 z + 0.6 ) } \end{array} \right.$$
$\left(y+5\right)^{2},\ \frac{\left(18m-n\right)^{2}}{4},\ \frac{9z^{2}}{4}-0.36$
