ANSWER
The coordinates of the image are (2,2)
EXPLANATION
The mapping for a reflection across the line y=k is :

We want to find the image of the point (2,-4) after a reflection in the line y=-1.
In this case k=-1.

This simplifies to,


Hence the image is (2,2)
The function and the first value stated for x are confusing.
Doing some research, I found that the problem is to evaluate the function

for x = - 1 and x 2.
The solution is:
1) For x = - 1

2) For x = 2
Answer:
x = (5/3 , 7)
Step-by-step explanation: