Question

Розв’яжіть рівняння:
х²+5х+6=0
2х²-х-6=0
(6х-7)(8х+1)=(8х+1)²

Answer 1

Объяснение:

1. ${x}^{2} + 5x + 6 = 0 \\ {x}^{2} + 2x + 3x + 6 = 0 \\ x(x + 2) + 3(x + 2) = 0 \\ (x + 3)(x + 2) = 0 \\ x = - 2 \\ x = - 3$

1. $2 {x}^{2} - x - 6 = 0 \\ 2 {x}^{2} - 4x + 3 x - 6 = 0 \\ 2x(x - 2) + 3(x - 2) = 0 \\ (2x + 3)(x - 2) = 0 \\ x = - 1.5 \\ x = 2$

1. $(6x - 7)(8x + 1) = {(8x + 1)}^{2} \\ (6x - 7)(8x + 1) - {(8x + 1)}^{2} = 0 \\ (8x + 1)(6x - 7 - 8x - 1) = 0 \\ (8x + 1)( - 2x - 8) = 0 \\ x = - \frac{1}{8} \\ x = - 4$