Explicație pas cu pas:
[tex] \frac{7}{4} - \frac{x}{3} = \frac{9}{2} [/tex]
[tex] \frac{21 - 4x}{12} = \frac{9}{2}[/tex]
[tex]2(21 - 4x) = 12 \times 9[/tex]
[tex]42 - 8x = 108[/tex]
[tex] - 8x = 108 - 42[/tex]
[tex] - 8x = 66 \\ x = - \frac{66}{8} \\ [/tex]
[tex]x = - \frac{33}{4} [/tex]
