Having trouble using law of sines

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I have a triangle like this and I must find the length of the unkown side with question mark:

Exercises from Khan Academy

And I am using law of sines like this:

$$ \dfrac{\sin 55^\circ}{2} = \dfrac{\sin 35^\circ}{x} $$ then we got this equation $$ x = \dfrac{2\sin 35^\circ}{\sin 55^\circ} $$ and it gives me the answer $ x \approx 1.40 $

But when I use this equation:

$$ \tan 35^\circ = \dfrac{x}{2} $$ $$ x = \dfrac{2}{\tan 35^\circ} $$

I get this answer: $ x \approx 2.85 $

Did I miss something?

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You're last step is incorrect.

$$\tan 35^\circ = \frac{x}{2}$$

is equivalent to

$$x = 2 \tan 35^\circ$$

which does give the same result.