I WILL MARK YOU AS BRAINLIEST!PLEASE HELP ME WITH 19

Answer:
x is 7.5 so the answer is D
Step-by-step explanation:
Since the triangles are similar, you can flip the 1st one to match the 2nd.
Now you can write
16/12=10/x
(the 9 is irrelevant)
now cross multiply to solve for x
12x10=120
120/16=7.5
x is 7.5