Answer: 9.708 cm
Explanation:
We will use sine as hypotenuse and angle is present and we need to find x
You have marked the sides wrong, the x side is opposite and the lower side is adjacent since the angle is opposite to x (facing x)
sin(theta) = opp/hyp
sin(54) = x/12
x = 12 * sin(54)
x = 9.708 cm