Here is the picture:
v=16 and w=25 and d is the angle of reference. I have to find ∠ADC.
Here is what I have done:
$\frac {sin(∠adc)}{25}$=$\frac {sin(30)} {16}$
sin(∠adc)=$\frac {25sin(30)} {16}$
∠adc=arcsin($\frac {25sin(30)} {16}$)
∠adc = 51.4
which means that ∠ADC=51.4. It is pretty obvious that it is incorrect because of the look of the angle. What did I do wrong and how do I find the right answer?

If $0\leq a\leq 1$ the equation: $$\sin x = a$$ has two solutions in $[0,\pi]$, namely $x_1 = \arcsin a$ and $x_2 = \pi -x_1$.