Looking at the table, we can see that at y = 7, the other y-values are equidistant from 7.
For example, the two points (52.5, 12) and (157.6, 12) are both 5 horizontal units away from (105, 7). In addition, the points (0, 27) and (210, 27) are both 20 horizontal units from (105, 7)
Hence, the vertex of the parabola is found at this point (105, 7).