The absolute values of two numbers that are additive inverses will be the same.

A number and its additive inverse are always the same distance from zero, and so they have the same absolute value.

Step-by-step explanation:

other dude said so

for finding the midpoint of any given 2 pair of points simply add the respective x coordinates with other x coordinate and the y coordinate with other y coordinate and divide them by 2

in your question it will be :

(3+1)/2 for the x coordinate of mid point i.e 2

[8+(-4)]/2 for the y coordinate of midpoint i.e 2

so coordinates of mid point of points (3,8) and (1,-4) will be (2,2)