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Problems
Contests
National and Regional Contests
Turkey Contests
National Olympiad First Round
2009 National Olympiad First Round
17
17
Part of
2009 National Olympiad First Round
Problems
(1)
Equilateral ABC, AD=8, BD = 13, DC=?
Source: 0
4/28/2009
A
B
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ABC
A
BC
is an equilateral triangle.
D
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D
is a point inside
△
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\triangle ABC
△
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BC
such that AD \equal{} 8, BD \equal{} 13, and \angle ADC \equal{} 120^\circ. What is the length of
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C
DC
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C
?
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<span class='latex-bold'>(A)</span>\ 12 \qquad<span class='latex-bold'>(B)</span>\ 13 \qquad<span class='latex-bold'>(C)</span>\ 14 \qquad<span class='latex-bold'>(D)</span>\ 15 \qquad<span class='latex-bold'>(E)</span>\ 16
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16