Question

Need help do not understand. Trig confused on what formula I should use?

Answer 1

In this triangle, you have

$\sin35^\circ=\dfrac{12}x\implies x=\dfrac{12}{\sin35^\circ}\approx20.9$

(Think sine = opposite/hypotenuse. The leg opposite the labeled angle has length 12, and the hypotenuse is $x$.)