Answer with Step-by-step explanation:
If the mid point of (x1,y1) and (x2,y2) is (a,b)
Then,

Here we are given that M is a mid point of P and let Q be another end point
i.e. (a,b)=(8,2)and (x1,y1)=(5,6)
We have to find (x2,y2)

16=5+x2 and 4=6+y2
x2=16-5 and y2=4-6
x2=11 and y2= -2
Hence, coordinate of other mid point is:
(11,-2)