Difference between revisions of "2014 AMC 8 Problems/Problem 9"

Line 7: Line 7:
 
draw(A--B--C--A);
 
draw(A--B--C--A);
 
draw(D--B);
 
draw(D--B);
dot("$A$", A, SW);
+
dot("<math>A</math>", A, SW);
dot("$B$", B, NE);
+
dot("<math>B</math>", B, NE);
dot("$C$", C, SE);
+
dot("<math>C</math>", C, SE);
dot("$D$", D, S);
+
dot("<math>D</math>", D, S);
label("$70^\circ$",C,2*dir(180-35));\</asy>
+
label("<math>70^\circ</math>",C,2*dir(180-35));\<\asy>
  
 
<math>\textbf{(A) }100\qquad\textbf{(B) }120\qquad\textbf{(C) }135\qquad\textbf{(D) }140\qquad \textbf{(E) }150</math>
 
<math>\textbf{(A) }100\qquad\textbf{(B) }120\qquad\textbf{(C) }135\qquad\textbf{(D) }140\qquad \textbf{(E) }150</math>

Revision as of 18:23, 26 November 2014

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("$A$", A, SW); dot("$B$", B, NE); dot("$C$", C, SE); dot("$D$", D, S); label("$70^\circ$",C,2*dir(180-35));\<\asy>

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