In the name of an angle the vertex of an angle is always written at the -------- No. Of altitudes in a triangle Interesting lines point of concurrence of altitudes All the points lie on the same line no. Of angles in a quadrilateral In a ∆ the angle opposite to the base centroid Median means Ray PQ and QP are different T/F concurrent lines End points of line In ∆ABC side opposite to vertex A No. Of medians in a triangle length of a ray In ∆ ABC Vertex opposite to side CA Parallel lines Altitude means Common initial point of two rays forming an angle no. Of vertices in a triangle Two rays forming an angle are called no. Of sides in a Pentagon In a∆ side opposite to the vertical angle 7 sided polygon end points of a line