Question

помогите срочно решить уравнения! 2) 3x(в квадрате) + 5x = 0 ;3) x(в квадрате) - 5x - 24 = 0;4) 2x(в квадрате) + 13x + 6 = 0;5) 7x(в квадрате) - 6x + 2 = 0; 6) 4x(в квадрате) + 12x + 9 = 0

Answer 1

$1)3 {x}^{2} + 5x = 0 \\ x(3x + 5) = 0 \\ x = 0 \\ 3x + 5 = 0 \\ 3x = - 5$

$x = - \frac{5}{3} = - 1 \frac{2}{3}$

$3){x}^{2} - 5x - 24 = 0 \\ d = 25 + 96 = 121 = 1 \\ x1 = \frac{5 + 1}{2} = 3$

$x2 = \frac{5 - 1}{2} = 2$

4)

$2 {x}^{2} + 13x + 6 = 0 \\ d = 169 - 48 = 121 = 11 \\ x1 = \frac{ - 13 - 11}{4} = - 6$

$x2 = \frac{ - 13 + 11}{4} = - \frac{ 2}{4} = - 0.5$

$5)7 {x}^{2} - 6x + 2 = 0 \\ d = 36 - 36 = 0 \\ x = \frac{6 + 0}{14} = \frac{6}{14} = \frac{3}{7}$

6)

$4 {x}^{2} + 12x + 9 = 0 \\ d = 144 - 144 = 0 \\ x = \frac{ - 12 + 0}{8} = - \frac{12}{8} = - 1 \frac{4}{8}$

$= - 1.5$