The formula of an area of a triangle:

We have:

substitute:

The formula of an area of a circle:

We have 
Substitute:

The area of the shaded region

Answer:
-19
Step-by-step explanation:
-2 and+2 =0
1/2 -3/2= -2/2 or -1
7-1=6
Answer:
18.95%
Step-by-step explanation:
In this case what we must do is calculate the probability of eating a jelly treats first and then another jelly treats, being the final probability the multiplication of these events.
We know that there are 20 in total and that initially there are 9 jelly treats, so the first event is the probability:
9/20
And the second event, with one less in each, would be:
8/19
The final probability then:
9/20 * 8/19 = 0.1895
So the probability of this happening is 18.95%