Are you sure that’s the question?
Since, the coordinates of the midpoint of line RS are M
.
The coordinates of endpoint R are (-2,10)
We have to determine the coordinates of endpoint S.
The midpoint of the line segment joining the points
and
is given by the formula
.
Here, The endpoint R is (-2,10) So, 
Let the endpoint S be 
The midpoint coordinate M is
.
So, 


Now, 


So, the other endpoint S is (8,0).
It beats 44 times in a minute
132 / 3 = 44
The slope would be y/x = 3/1 = 3