So according to question, what values of $\cot (x)$? So I've tried and got $\frac{-1}{4}$ Thanks for helping!
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1How did you reach that value? Showing your working will help people spot if you have gone wrong, or confirm you are correct – lioness99a May 30 '17 at 10:06
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yes you are right. it's mb – Physicer May 30 '17 at 10:37
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Produce $AE$ and $BC$ to meet at $K$. Then $\triangle KEC\sim\triangle KAB$. As $EC:AB=2:6=1:3$, we have $KC:KB=1:3$ and hence $KC=3$. So $\displaystyle \tan\angle KEC=\frac{2}{3}$ and $\displaystyle \tan\angle KBF=\tan\angle AFB=\frac{6}{3}=2$. Note that $x=\angle KEC+\angle KBF$.
\begin{align*} \tan x&=\frac{\tan\angle KEC+\tan\angle KBF}{1-\tan\angle KEC\tan\angle KBF}\\ &=\frac{\frac{2}{3}+2}{1-(\frac{2}{3})(2)}\\ &=-8 \end{align*}
$\displaystyle \cot x=\frac{-1}{8}$.
CY Aries
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