Is this geometry ques. bad or my thinking process is wrong?

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Junior | Next Rank: 30 Posts
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If CD = 6, what is the length of BC?

1) BD = 6 radical 3

2)x = 60 degrees.

I thought st. 1 is not suff., but it turns out it is.

oa D

Thanks in advance.

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by xcusemeplz2009 » Fri Nov 13, 2009 7:40 pm
for 2nd)

x=sum of interior opp angles

using this formula we can get the other angle as 30 and hence the req side as same as 6
It does not matter how many times you get knocked down , but how many times you get up

Junior | Next Rank: 30 Posts
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by Lance123 » Fri Nov 13, 2009 9:09 pm

I believe once it is possible to determine the length of 2 sides of the triangle and the angled formed by these 2 side, then it is sufficient.

Also, if you know all 3 of the angles as well as the length of 1 side, this is also sufficient.

In both cases, the Triangle is fixed, and only one such triangle can exist.