Question

Решите пожалуйста очень нужно плисс даю 20 баллов​

Answer 1

Объяснение:

${x}^{2} - 5x + 4 = 0 \\ d = 25 - 4 \times 1 \times 4 = 9 \\ \sqrt{d} = 3 \\ x1 = \frac{ - 5 + 3}{2} = 1 \\ x2 = \frac{ - 5 - 3}{2} = - 4$

${y }^{2} + 9y = 0 \\ y(y + 9) = 0 \\ \\ y = 0 \\ \\ y + 9 = 0 \\ y = - 9$

$2 {t}^{2} - 72 = 0 \\ 2 {t}^{2} = 72 \\ {t}^{2} = 36 \\ \\ t = 6 \\ \\ t = - 6$

$7 {z}^{2} - z - 8 = 0 \\ d = 1 - 4 \times 7 \times ( - 8) = 1 + 224 = 225 \\ \sqrt{d} = 15 \\ z1 = \frac{8}{7} \\ z2 = - 1$

${m}^{2} - 7m + 6 = 0 \\ d = 49 - 4 \times 1 \times 6 = 25 \\ \sqrt{m } = 5 \\ m1 = 1 \\ m2 = 6$

${x}^{2} - 6x = 0 \\ x(x - 6) = 0 \\ \\ x = 0 \\ \\ x - 6 = 0 \\ x = 6$

$6 {y}^{2} + y - 7 = 0 \\ d = 1 - 4 \times 6 \times ( - 7) = 1 - 24 \times ( - 7) =1 + 168 = 169 \\ \sqrt{d} = 13 \\ y1 = - \frac{7}{6} \\ y2 = - 1$

$5 {t}^{2} - 125 = 0 \\ 5 {t}^{2} = 125 \\ {t}^{2} = 25 \\ \\ t = 5 \\ \\ t = - 5$