Ответ:

[tex] \frac{0.3}{0.8x - 3} = \frac{ - 9}{0.6x - 8.4} [/tex]

0,3×(0,6x-8,4)=-9×(0,8x-3)

0,18x-2,52=-7,2x+27

0,18x+7,2x=27+2,52

7,38x=29,52

x=29,52÷7,38

x=4