Answer:
12.4
Step-by-step explanation:
Solving for the last degree on the triangle, it would be
180 - 54 - 90 = 36.
Using the law of sines, we can get that
sin(54)/x = sin(36)/9 (degrees)
sin(54)/x = 0.065309
sin(54)/0.065309 = x
x = 12.3874, which is around 12.4
We can check our work by seeing if the two equations are equal.
sin(54)/12.4 = 0.065243, which is close enough to 0.065309.
