The answer is: [A]: 45x² + 81x + 36 .
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Explanation: Use "FOIL" technique: (First, Outer, Inner, and Last Terms);
then, combine the "like terms", to simplify.
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(5x+4)(9x+9) = 45x² + 45x + 36x + 35 = 45x² + 81x + 36 .
(which is answer choice: "A".).
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They are vertical angles, thus they are equal to each other:
5x + 12 = 6x - 10
22 = x
x = 22
There were 80 questions on the test.
Answer:



Arithmetic sequence
Step-by-step explanation:
We are given that
A(1)=9
We have to find first three terms and identify the sequence is geometric or arithmetic.
Substitute n=1
Then, we get

For n=2

For n=3





When the difference of consecutive terms are constant then the sequence is arithmetic sequence.
Therefore, given sequence is arithmetic sequence.