Answer:
x = -3
Step-by-step explanation:
[tex] \frac{1}{3} -(21 - 3x) = \frac{1}{2} (8 - 4x)[/tex]
[tex]21 - 3x = 3(4 - 2x)[/tex]
[tex]21 - 3 x = 12 - 6x[/tex]
[tex] - 3x + 6x = 12 - 21[/tex]
[tex]3x = - 9[/tex]
[tex]x = - 3[/tex]