2014 AMC 8 Problems/Problem 9

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In $\bigtriangleup ABC$, $D$ is a point on side $\overline{AC}$ such that $BD=DC$ and $\angle BCD$ measures $70^\circ$. What is the degree measure of $\angle ADB$?

[asy]size(300);defaultpen(linewidth(0.8));pair A=(-1,0),C=(1,0),B=dir(40),D=origin;draw(A--B--C--A);draw(D--B);dot("$A$"...[/asy]

$\textbf{(A) }100\qquad\textbf{(B) }120\qquad\textbf{(C) }135\qquad\textbf{(D) }140\qquad \textbf{(E) }150$