Answer: I believe this is the answer.

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7 and -6
or
-7 and 6
Answer:
See explanation
Step-by-step explanation:
Plot the solution sets to both inequalities.
1. For the inequality
First, plot the dotted line
(dotted because sign is without notion "or equal to"), then choose correct part by substitution coordinates of the origin.

so the origin does not belong to the needed part. Shade the part, which does not include origin.
2. For the inequality
First, plot the dotted line
(dotted because sign is without notion "or equal to"), then choose correct part by substitution coordinates of the origin.

so the origin does not belong to the needed part. Shade the part, which does not include origin.
3. Find the common region of these two shaded parts - this is the solution to the system of two inequalities.
So you will need to solve for x and y before evaluating 2x+y....
2x-y=9, y=2x-9 now this will make 4x^2-y^2=171 become:
4x^2-(2x-9)^2=171
4x^2-(4x^2-36x+81)=171
36x-81=171
36x=252
x=7, now we can use 2x-y=9 to solve for y...
2(7)-y=9
14-y=9
-y=-5
y=5
now we know that x=7 and y=5, 2x+y becomes:
2(7)+5
14+5
19
Answer: 13300
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Work Shown:
A = event that it rains
B = event that it does not rain
P(A) = 0.30
P(B) = 1-P(A) = 1-0.30 = 0.70
Multiply the attendance figures with their corresponding probabilities
- if it rains, then 7000*P(A) = 7000*0.30 = 2100
- if it doesn't rain, then 16000*P(B) = 16000*0.70 = 11200
Add up the results: 2100+11200 = 13300
This is the expected value. This is basically the average based on the probabilities. The average is more tilted toward the higher end of the spectrum (closer to 16000 than it is to 7000) because there is a higher chance that it does not rain.