Answer:
The question doesn’t state what T represents, so I will assume T is one of two points:
1. The midpoint of R and S, or
2. S is the midpoint of RT.
1. T((-9+2)/2,(4-1)/2)=T(-7/2,3/2)
2. T(x,y): S(2,-1)=((-9+x)/2,(4+y)/2); 2=(-9+x)/2, 4=-9+x, x=13; (4+y)/2=-1, 4+y=-2, y=-6. T(13,-6)
