Final answer:
The centroid divides the medians of a triangle in a 2:1 ratio. Given that UJ is twice VJ, the correct lengths would maintain this ratio. The question seems to contain errors in lengths, but an understanding of the properties of centroids allows for correction.
Step-by-step explanation:
The centroid of a triangle (denoted as J in this case) divides the medians into two segments, one of which is twice as long as the other. The longer segment extends from the vertex of the triangle to the centroid, and the shorter segment extends from the centroid to the midpoint of the opposite side. In the given question, J is the centroid, and UJ is twice as long as VJ, because VJ is the segment from the centroid to the midpoint of the side UZ. If UJ is 9 units long, then VJ (the shorter segment) is 9 units divided by 2, which is 4.5 units long. This is not the same length given in the question, so we must correct the given lengths based on the properties of centroids.