Answer:
a=-2
So yep. ;)
Step-by-step explanation:
Alright, so, (2,12), 2 is the x and 12 is the y.
Stick them into the equation: 
Then, solve:

a = -2
So yes, they're on the graph.
Hope this helped! :)
Answer:
C. Adjacent
Step-by-step explanation:
It’s in the picture , i hope this helped you
18. 0.0011
20. 1/625
19. 0.0011
21. 1/27
Rounded to the nearest whole number would be 426