Answer:
none of them.
Step-by-step explanation:
A. 7 and 4 can not go into 30
B & D are the same choice and LCD is 15
C. LCD is 15
X-30+x-30+x=180
3x-60=180
3x=240
X=80
Rational because it is an integers and integers are negitive numbers
For this case we have the following functions:

The first thing we must do is calculate the sum of functions or equivalently:

We have then:

To complete the sum, we must add the terms whose exponents are equal.
We have then:

Then, we evaluate the function for x = 2:

Rewriting we have:
Answer: