The sequence seems to be that you add 1 and then multiply by 2, and then add 1 and multiply by 3, so I would assume you do 9 + 1 = 10, and then multiply by 4 to get 40 as your next number. I hope this helps!
Problem 11
<h3>Answer: h =
2A/b</h3>
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Explanation:
We need to get h by itself. To do so, we first multiply both sides by 2. Then we divide both sides by b
A = (1/2)*b*h
2A = b*h
b*h = 2A
h = 2A/b
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Problem 12
<h3>Answers:</h3>
- Equation: (n+2)/5 = 14
- Solution to that equation: n = 68
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Explanation:
The number n is increased by 2 to get n+2
Then we divide by 5 to get (n+2)/5
This is set equal to 14 to get the equation (n+2)/5 = 14
Solving the equation would look like this
(n+2)/5 = 14
n+2 = 5*14 .... multiply both sides by 5
n+2 = 70
n = 70-2 .... subtract 2 from both sides
n = 68
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Problem 13
<h3>Answer: Not a solution</h3>
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Explanation:
We'll replace every copy of x with -3 and simplify
-2x + 5 > 13
-2*(-3) + 5 > 13
6 + 5 > 13
11 > 13
The last inequality is false because 11 is not greater than 13. Since the last inequality is false, this makes the first inequality false when x = -3.
Therefore, x = -3 is not a solution.
Answer: D
Step-by-step explanation: 
1. 4800-2000=2800
This is the distance that the balloon needs to fall to reach an altitude of 2000 feet.
2. 2800/40=70
Distance/rate=time
The answer is 70 minutes.