I FOUND YOUR COMPLETE QUESTION IN OTHER SOURCES.
PLEASE SEE ATTACHED IMAGE.
For this case what you should do is use the following trigonometric relationship:
sine (theta) = C.O / h
Where,
theta: angle
C.O: opposite leg
h: hypotenuse
Substituting values we have:
sine (80) = 9 / x
Answer:
sine (80) = 9 / x
