Difference between revisions of "2015 AMC 12B Problems/Problem 13"

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==Problem==
 
==Problem==
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Quadrilateral <math>ABCD</math> is inscribed in a circle with <math>\angle BAC=70^{\circ}, \angle ADB=40^{\circ}, AD=4,</math> and <math>BC=6</math>. What is <math>AC</math>?
  
 
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<math>\textbf{(A)}\; 3+\sqrt{5} \qquad\textbf{(B)}\; 6 \qquad\textbf{(C)}\; \dfrac{9}{2}\sqrt{2} \qquad\textbf{(D)}\; 8-\sqrt{2} \qquad\textbf{(E)}\; 7</math>
  
 
==Solution==
 
==Solution==

Revision as of 23:49, 3 March 2015

Problem

Quadrilateral $ABCD$ is inscribed in a circle with $\angle BAC=70^{\circ}, \angle ADB=40^{\circ}, AD=4,$ and $BC=6$. What is $AC$?

$\textbf{(A)}\; 3+\sqrt{5} \qquad\textbf{(B)}\; 6 \qquad\textbf{(C)}\; \dfrac{9}{2}\sqrt{2} \qquad\textbf{(D)}\; 8-\sqrt{2} \qquad\textbf{(E)}\; 7$

Solution

See Also

2015 AMC 12B (ProblemsAnswer KeyResources)
Preceded by
Problem 12
Followed by
Problem 14
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
All AMC 12 Problems and Solutions

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