Answer:
B(2,4)
Step-by-step explanation:
A(-1,-9)
M(0.5,-2.5)
with M we can find x₂ and y₂
x = 0.5
x = x₁+x₂/2
0.5 = (-1 + x₂)/2
(x₂ -1)/2 = 0.5
x₂-1=0.5×2
x₂-1=1
x₂=2
for y₂
y= -2.5
y=(y₁+y₂)/2
y=(-9+y₂)/2
-2.5=(-9+y₂)/2
-9+y₂=-2.5×2
-9+y₂=-5
y₂=-5+9
y₂=4
.: coordinates are B(2,4).
