Answer:
B and C work. A and D do not.
Explanation:
This is one of those questions that you have to go through each answer to see what the results are. You don't have to go far to eliminate A and D so let's do that first.
A]
5n + 6
Let n = 1
5(1) + 6
5 + 6= 11
However there is trouble beginning with n = 2
5*2 + 6
10 + 6
16 All you need is one wrong answer and the choice is toast. So A won't work.
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Try D
6(n - 1)+ 5
n=0
6*(-1) + 5
-6 + 5
- 1
And D has been eliminated with just 1 attempt. n= 2 or n = 1 would be even worse. D is not one of the answers.
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B
Let n = 1
6(1) + 5
6 + 5
11 The first term works.
n = 2
6*(2) + 5
12 + 5
17 and n = 2 works as well. Just in case it is hard to believe, let's try n = 3 because so far, everything is fine.
n = 3
6*(3) + 5
18 + 5
23 And this also works. I'll let you deal with n = 4
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C
n = 0
6(0 + 1) + 5
6*1 + 5
6 + 5
11
n = 1
6(1 + 1) + 5
6*2 + 5
12 + 5
17 which works.
So C is an answer.