Understand what exactly??
The correct answer is B. -4<x<2.
This is because the domain is looking for the values of x that can be used in the function. In the picture below, you will notice that the leftmost point is at x = -4. This is as low as the x value goes. The rightmost point is at x = 2, which is as large as the x value gets. Therefore the domain is between those two numbers.
Okay, so my last answer was deleted because I didnt show any work.
According to the rule,
a+b>c
c+b>a
c+a>b
so...
2+3=6...6<7
21+23=44...44+44
12+36=48...48<53
14+17=31...31>30
Since answer D is the only answer that fullfills the rule a+b>c, it is the correct answer
