The Co-ordinate of point X is X(2,-3)
The quadrilateral is reflecting across the line X=- 3.
So the new reflected coordinates of the point X is given as follows.
X(-3-(2+3) , -3) = X(-8, -3)
So the answer is (-8,-3).
(-8, -3) is the location of point X after the reflection about X= -3.