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What is the degree of $\angle AFC$?

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I have tried this, but it seems do not work

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Your help is appreciated!

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We know that $\widehat{CAB}=\widehat{CAF}+\widehat{FAB}=80^\circ$ and by Trig Ceva's theorem $$ \frac{\sin\widehat{CAF}}{\sin\widehat{FAB}}\cdot\frac{\sin 10^\circ}{\sin 20^\circ}\cdot\frac{\sin 30^\circ}{\sin 40^\circ}=1\tag{1} $$ holds. $\widehat{CAF}=60^\circ$ and $\widehat{FAB}=20^\circ$ meet every constraint, hence $$ \widehat{CFA}=\color{red}{80^\circ}.\tag{2}$$

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