Let's see. From the looks of things you have a .
I can tell that is vertical since the x-coordinates are the same. I can also tell that is horizontal since the y-coordinates are the same.
The right angle is at A.
The hypotenuse is
Use the distance formula:
to find the length of
Now find the midpoint M of using the midpoint formula:
is the median drawn from the right angle to the midpoint of the hypotenuse M
Next use the distance formula again to find the length of and see if it is half of