Nine is the answer cuz it equals 27 then subtract 2 equals 24
I)
The Midpoint M of the line segment AB is found using the Midpoint formula:

ii)
the slope of the line through A and B is found by the slope formula:

iii)
the product of the slopes of 2 perpendicular lines is -1, so the slope of the line perpendicular to the line through A and B is -1/(-1)=1
iv)
the equation of the line with slope 1, which contains point M(3, 9) is found by the slope point form equation of a line:
y-9=1(x-3)
y-9=x-3
y=x+6
Answer: y=x+6
The midpoint formula is basically (averaging the x coordinates, averaging the y coordinates).
Point A: (3, 7)
Point B: (2, -1)
Midpoint x: (3 + 2) / 2 = 5 / 2
Mindpoint y: (7 - 1) / 2 = 3
Therefore, the midpoint of the segment is choice C (5/2, 3)