The midpoint formula is

So just plug in the corresponding coordinates in the correct place to get the midpoint.
x_1=-5 ; x_2=9 ; y_1=-5 ; y_2=5
((-5 + 9)/2 , (-5 + 5)/2)
(4/2 , 0/2)
(2,0) is where Kenya's house is(which is the midpoint).
The distance formula is a bit more complicated than that. The distance formula is D=

In this case now, your looking for the distance from Hannah's house to Kenya's house.
D=

=

=

≈8.6023