\[\frac{2x^{2} + 9x - 18}{4x^{2} - 9} =\]
\[= \frac{2 \cdot (x - 1,5)(x + 6)}{(2x - 3)(2x + 3)} =\]
\[2x^{2} + 9x - 18 = 0\]
\[x_{1} + x_{2} = - 4,5\]
\[x_{1} \cdot x_{2} = - 9\]
\[\Longrightarrow x_{1} = 1,5;\ \ x_{2} = - 6.\]
\[2x^{2} + 9x - 18 =\]
\[= 2 \cdot (x - 1,5)(x + 6) =\]
\[= (2x - 3)(x + 6).\]