ANSWER
The greatest common factor is

EXPLANATION
We want to find the greatest common factor of

and

The prime factorizations are;

and

The product of the least powers of the common factors is the greatest common factor.
Answer:
n = 19.89694
Step-by-step explanation:
You can work the problem using decimal numbers. There is no need to convert everything to integers. Trying to do so just gets you in trouble.
Subtract 2.2 from both sides:
-1.398 -2.200 = n/-5.53
-3.598 = n/-5.53
Now, multiply both sides by -5.53:
(-5.53)(-3.598) = n = 19.89694
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The one rule that cannot be violated in algebra is that <em>you must do the same thing to both sides of the equation</em>.
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Your "solution" so far has a couple of errors. The first is that you have apparently multiplied all of the numbers by 1000. Unfortunately, when you multiply a denominator by 1000, it is the same as dividing by 1000. So, you have multiplied the left side by 1000, multiplied one term on the right by 1000 and divided another term on the right by 1000. This turns the equation into something different than what you started with, and will give a wrong answer.
The second error is that you have subtracted 2200 only from the right side. This, too, will turn the equation into something different than what you started with, and will give a wrong answer.
A
Explanation-
Domain is the X, which is also independent. So you look at the first circle, or in more detail, the circle that has arrows pointing AWAY from it.