Ответ:
\[5x^{2} - 4x = 15x\]
\[5x^{2} - 19x = 0\]
\[5x\left( x - \frac{19}{5} \right) = 0\]
\[x = 0;\ \ x = \frac{19}{5} = 3,8.\]
\[5x^{2} - 4x = 15x\]
\[5x^{2} - 19x = 0\]
\[5x\left( x - \frac{19}{5} \right) = 0\]
\[x = 0;\ \ x = \frac{19}{5} = 3,8.\]