ОДЗ
x ≠ 0; x ≠ - 10
120*5(x + 10) - 120*5*x - 2x (x + 10) = 0
600x + 6000 - 600x - 2x^2 - 20x = 0
- 2x^2 - 20x + 6000 = 0 /:(-2)
x^2 + 10x - 3000 = 0
D = 100 + 12000 = 12100 = 110^2
x1 = ( - 10 + 110)/2 = 100/2 = 50
x2 = ( - 10 - 110)/2 = - 120/2 = - 60
ОТВЕТ
- 60; 50