Answer:
B. (-2, 3)
Explanation:
Given two coordinates (x₁, y₁) and (x₂, y₂), the coordinate of their midpoint is equivalent to X = (x₁+x₂)/2 and Y = (y₁+y₂)/2.
Given the coordinate of Sally's house and her school to be (5, −1) and (−9, 7) respectively, the midpoint of Sall's house and school is expressed as shown;
from the coordinates, x₁ = 5, y₁ = -1, x₂ = -9 and y₂ = 7
X = (5+(-9))/2
X = 5-9/2
X = -4/2
X = -2
Y = -1+7/2
Y = 6/2
Y = 3
The coordinate of the midpoint of Sally's house and school will be expressed as (X, Y) which is equivalent to (-2, 3).