The midpoint is the average of the endpoint coords. If (x,y) is F, then -6=(-14+x)/2 and 7=(13+y)/2. -14+x=-12 so x=2, and 14=13+y, so y=1 and F is (2,1). so the answer is (2,1)
The question involved the concept of combination because the order of the friends being picked are not considered. There are a total of 8 friends and 5 out of them are picked. 8C5 = 56 Therefore, there are 56 ways.