We know that
[tex]\vec{BD}\text{ bisects }\angle ABC[/tex]That means
[tex]m\angle ABD=m\angle CBD[/tex]So,
[tex]\begin{gathered} (6x+14)^{\circ}=(3x+29)^{\circ} \\ 6x+14=3x+29 \\ 6x-3x=29-14 \\ 3x=15 \\ x=\frac{15}{3}=5 \end{gathered}[/tex]If
[tex]\begin{gathered} \vec{BD}\text{ bisects }\angle ABC \\ \text{then} \\ m\angle ABC=m\angle ABD+m\angle CBD \end{gathered}[/tex]Finally,
[tex]m\angle ABD=(6x+14)^{\circ}=(6\cdot5+14)^{\circ}=44^{\circ}[/tex][tex]m\angle CBD=(3x+29)^{\circ}=(3\cdot5+29)^{\circ}=44^{\circ}[/tex][tex]m\angle ABC=44^{\circ}+44^{\circ}=88^{\circ}[/tex]