Answer:

Explanation:
If two points are given as 
 (point 1) and 
 (point 2), then the midpoint of these 2 points are given by the formula:
Midpoint = 

Using R as point 1 , S as point 2, and T as midpoint, we can substitute in the formula and get 2 equations shown below:
 * This is equation 1 from which we can find 

 * This is equation 2 from which we can find 

Solving equation 1:

Solving equation 2:

Hence the coordinates of point S is 
