Answer:
The coordinates of R are

Explanation:
Given : M(5, 7) is the midpoint of RS. The coordinates of S are (6, 9).
To find : What are the coordinates of R?
Solution :
We have given,
A line RS which has a mid point M.
Let, the coordinates of R be

The coordinates of S are

The coordinates of M are

Applying mid-point formula,


Solve separately,
x- coordinate is



y- coordinate is



So, The coordinates of R are
