Question

помогите срочно с 1 и 2 заданием

Answer 1

Ответ:

1)

a)

${x}^{2} + 7x + 10 = 0 \\ d = 49 - 4 \times 10 = 49 - 40 = 9 = {3}^{2} \\ x1 = \frac{ - 7 + 3}{2} = - \frac{4}{2} = - 2 \\ x2 = \frac{ - 7 - 3}{2} = - \frac{10}{5} = - 2$

б)

${x}^{2} - 2x + 1 = 0 \\ d = 4 - 4 = 0 \\ x = \frac{2 + 0}{2} = \frac{2}{2} = 1$

2)

${x}^{2} - 8x + 15 = 0 \\ x1 + x2 = 8 \\ x1 \times x2 = 15 \\ x1 = 3 \\ x2 = 5$