whats the length of BC

http://i47.tinypic.com/11jyhkh.jpg

A. 5 B. 20 C. 15 D. 30

Question

whats the length of BC

http://i47.tinypic.com/11jyhkh.jpg

 A. 5 B. 20 C. 15 D. 30

saifoo.khan · Answer

Do you know the formula which relates b/w area and lengths?

saifoo.khan · Answer

$$\Large \frac{A_1}{A_2} = (\frac{L_1}{L_2})^2$$

saifoo.khan · Answer

Can you solve now?

anonymous · Answer

lol or you can just tell me. thanks for the help anyways.

saifoo.khan · Answer

Lol, i told u.. insert the values and solve.

anonymous · Answer

i got 10. and its not even on the choices fml.

saifoo.khan · Answer

Ok, so tell me what u did to solved? 
i will guide u step by step.

anonymous · Answer

its cool, i got the answer from somebody else.

saifoo.khan · Answer

BUt u did not learnt anythin. -_-

anonymous · Answer

nah brown niqqa, the worksheet f'd up and gave me the wrong multiple choices so i got the answer anyways. they didn't friggin square the problem. thanks for your concern doe

anonymous · Answer

ended up being 20 if you didn't sq are it