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
Three pieces are left. Hope this helps!
... Max sure is hungry.
You can create a right angled triangle.
Find the hypotenuse.
The third point of the triangle is (1,0)
using pythagoras, the value of a is 2, b is 3. 2^2 +3^2 = 13.
Therefore the distance between the two points is
715 miles / 11 hours = 65 mph
845 miles / 65 mph = 13 hours
It would take 13 hours to drive 845 miles.