Answer:
7
solution,
CD=3x-12
AB=14
BD=6
AC=21
Angle bisector theorem ,
[tex] \frac{ab}{bd} = \frac{ac}{cd} \\ \: or \: \frac{14}{6} = \frac{21}{3x - 12} \\ or \: 14(3x - 12) = 21 \times 6( \: cross \: multiplication) \\ or \: 42x - 168 = 126[/tex]
Adding 168 on both sides
[tex]or \: 42x - 168 + 168 = 126 + 168 \\ or \: 42x = 294[/tex]
dividing 42 on both side
[tex] \frac{42x}{42} = \frac{294}{42} \\ [/tex]
[tex]x = 7[/tex]
Hope this helps..
Good luck on your assignment..
