\[(a - 1)x^{2} + (2a - 3)x + a = 0;\ \ \ \ \]
\[a = 1\]
\[D = (2a - 3)^{2} - 4a(a - 1) =\]
\[= 9 - 8a\]
\[9 - 8a < 0\]
\[8a > 9\ \ \]
\[a > \frac{9}{8}\]
\[a > 1\frac{1}{8}\]
\[Ответ:a \in \left( 1\frac{1}{8};\ + \infty \right).\]