Question

решите уравнение
1) 7x^2 - 7x = 0;
2) -5x^2 - 125x = 0;
3) -28x^2 - 7x = 0.

Answer 1

Ответ:

$1) {7x}^{2} - 7x = 0 \\ 7x(x - 1) = 0 \\ 7x = 0 \\ x = 0 \\ x - 1 = 0 \\ x = 1 \\ 2)5 {x}^{2} - 125x = 0 \\ 5x(x - 25) = 0 \\ 5x = 0 \\ x = 0 \\ x - 25 = 0 \\ x = 25 \\ 3)$

$- 28 {x}^{2} - 7x = 0 \\ - 7x(4x + 1) = 0 \\ - 7x = 0 \\ x = 0 \\ 4x + 1 = 0 \\ 4x = - 1 \\ x = - \frac{1}{4}$