M is the midpoint of PQ and N is the midpoint of PR, and O is the intersection of QN and RM, as shown. If QN is perpendicular PR, QN = 12, and PR = 14, then find OR.

Answer:
OR = √65
Step-by-step explanation:
M and N are the midpoints of their respective sides, so O is the centroid of the triangle. That means ...
ON = QN/3 = 12/3 = 4
By the Pythagorean theorem, ...
OR² = NR² +ON²
OR² = 7² +4² = 65
OR = √65