Answer: Choice C. 
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Explanation:
The domain is the set of all allowed x inputs.
Here we see that x = -3 is the smallest x value possible as it is from the left-most point. The graph goes on forever to the right, so there is no largest x value. Effectively infinity is the largest x value even though infinity is not a number.
We can say the domain is
which can be simplified to
or 
In short: x can be -3 or larger.
To do this we need to find the factors of 60 these are:
1 and 60
2 and 30
3 and 20
4 and 15
5 and 12
6 and 10
There is 1 pair that have a difference of 7 and that is 5 and 12
A
substitute x = 3h into f(x)
f(3h) = 2(3h)² + 3(3h) - 4 = (2 × 9h²) + 9h - 4 = 18h² + 9h - 4
Answer:
It would've been more difficult to solve and doing it as shown in EX:2 it's a way easier method to use and remember.