Răspuns:
[tex] \frac{x}{3 + 2(x - 1) + 7} = 12[/tex]
[tex] \frac{x}{3 + 2x - 2 + 7} = 12[/tex]
[tex] \frac{x}{2x + 3 - 2 + 7} = 12[/tex]
[tex] \frac{x}{2x + 8} = \frac{12}{1} [/tex]
x = 12(2x + 8)
x = 24x + 96
x - 24x = 96
- 23x = 96
[tex]x = - \frac{96}{23} [/tex]