Asegment has endpoints a (-1, 1) and b (8, 4) . find the coordinates of the three points that divide the segment into four equal parts. (named from a to b, x y z) (use fraction format)

 You need to use Mid point formula for Q1 and 3 
Q.1) FIRST find out the midpoint of seg AB.. Lets call it as M.. then find midpoint of segAM and MB... 
these will br required M points.. 
Q.3) Simply use midpoint for all the sides 
MID-POINT formula is 
A =(x1 , y1) B = (x2 , y2) then M = [ (X1+X2) /2 , (Y1+Y2) /2 ] 
Q.2) find out the midpoint for a side and then find its distance from the opposite vertex.. that wil be length of that median.. do the same for all the three vertices... 

Bc equals mb that should be your answer