$5x^2 - 11x + 2 = 0$
$D = 11^2 - 4 * 5 * 2 = 81$
$x = \frac{11 ± \sqrt{81}}{2 * 5}$
$x_1 = \frac{11 - 9}{2 * 5} = \frac{2}{10} = 0,2$
$x_2 = \frac{11 + 9}{2 * 5} = \frac{20}{10} = 2$
Ответ:
$x_1 = 0,2$;
$x_2 = 2$.

$2p^2 + 7p - 30 = 0$
$D = 7^2 - 4 * 2 * (-30) = 289$
$x = \frac{-7 ± \sqrt{289}}{2 * 2}$
$x_1 = \frac{-7 - 17}{2 * 2} = \frac{-24}{4} = -6$
$x_2 = \frac{-7 + 17}{2 * 2} = \frac{10}{4} = \frac{5}{2} = 2\frac{1}{2}$
Ответ:
$x_1 = -6$;
$x_2 = 2\frac{1}{2}$.

$9y^2 - 30y + 25 = 0$
$D = 30^2 - 4 * 9 * 25 = 900 - 900 = 0$
$y = \frac{30}{2 * 9} = \frac{5}{3} = 1\frac{2}{3}$

$35x^2 + 2x - 1 = 0$
$D = 2^2 - 4 * 35 * (-1) = 144$
$x = \frac{-2 ± \sqrt{144}}{2 * 35}$
$x_1 = \frac{-2 - 12}{2 * 35} = \frac{-14}{70} = -\frac{1}{5}$
$x_2 = \frac{-2 + 12}{2 * 35} = \frac{10}{70} = \frac{1}{7}$
Ответ:
$x_1 = -\frac{1}{5}$;
$x_2 = \frac{1}{7}$.

$2y^2 - y - 5 = 0$
$D = 1^2 - 4 * 2 * (-5) = 1 + 40 = 41$
$y = \frac{1 ± \sqrt{41}}{4}$

$16x^2 - 8x + 1 = 0$
$D = 8^2 - 4 * 16 * 1 = 64 - 64 = 0$
$x = \frac{8}{2 * 16} = \frac{1}{4}$