First find SN length pythag theorem 4^4 + SN^2 = 22^2 SN = 21.6333 or 2 sqrt117
UM goes up sqrt117 units (Pythag theorem again with a line dropped from M) for a horizontal distance of 6 units
sqrt117/6 = NX/4 yields NX = 2/3 sqrt 117 sooooo SX = 2 sqrt 117 - 2/3 sqrt 117 = 4/3 sqrt(117) units (I think ! )
Not positive about this answer !
Important: The Median Theorem states that the medians of a triangle intersect at a point called the centroid that is two-thirds of the distance from the vertices to the midpoint of the opposite sides.
ST2 - TN2 = SN2
SX / NX = 2 / 1
SX = 2/3 * SN