Answer:
Explanation:
8. B is the midpoint of AD
A (x,y)
D( -1,3) B ( (x-1)/2, (y+3)/2) and B ( 1,1)
then (x-1)/2=1, x-1=2 ( +1) , x= 2+1, x=3
(y+3)/2=1, y+3=2 ( -3) y=2-3, y= -1
then A (3, -1)
9. (-8,3)
(s,3) the midpoint (0,u)
then (s-8)/2=0, s=8
(3+3)/2=u, u=6/2, u= 3
10. a=1 ( the y coordinate is the same as the midpoint
A(3,1)
B(x,y) the midpoint (5,1)
(3+x)/2=5, 3+x=10 , x=10-3, x=7
(y+1)/2=1, y+1=2,y=2-1, y=1
B(7,1)