Answer:
Circle
Step-by-step explanation:
I don't know if there is a more "professional" way to solve this, but I wrote out the pattern until I got to the twentieth shape and it ended up being a circle :)
most common, 4, c, 9
the value of x is 5 :) lalal
9/2
2+2+2+2=8
9-8=1
2 can go into 9 four whole times
4 1/2