\[\boxed{\mathbf{622\ (622).\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[1)\ \frac{1}{6}x² - 2x - 3 = 0\ \ \ | \cdot 6\]
\[x² - 12x - 18 = 0\]
\[2) - 4x^{2} + 20x - 16 =\]
\[= 0\ \ \ |\ :( - 4)\]
\[x^{2} - 5x + 4 = 0\]
\[3)\ 3x² + x + 2 = 0\ \ \ \ |\ :3\]
\[x^{2} + \frac{1}{3}x + \frac{2}{3} = 0\]