Question

Помогите пожалуйста решить номер 1184,1185,1186

Answer 1

Ответ:

1184.

$x {}^{2} + 17x = - 72 \\ x { }^{2} + 17x + 72 = 0 \\ d = 17 {}^{2} - 4 \times 72 = 1 \\ \\ a {1}^{} = \frac{ - 17 - 1}{2} = - 9 \\ \\ a {2}^{} = \frac{ - 17 + 1}{2} = 8$

1185.

$x {}^{2} - 3x = 40 \\ x { }^{2} - 3x - 40 = 0 \\ d = 9 + 4 \times 40 = 169 \\ \\ a {1}^{} = \frac{ 3 - 13}{2} = - 5 \\ \\ a {2}^{} = \frac{3 + 13}{2} = 8$

1186.

$x { }^{2} + 10x = - 16 \\ x {}^{2} + 10x + 16 = 0 \\ d = 100 - 4 \times 16 = 36 \\ \\ a {1}^{} = \frac{ - 10 - 6}{2} = - 8 \\ \\ a {2}^{} = \frac{ - 10 + 6}{2} = - 2$