where do the altitudes of a triangle intersect
Altitude (triangle) The three (possibly extended) altitudes intersect in a single point, called the orthocenter of the triangle, usually denoted by H.[1][2] The orthocenter lies inside the triangle if and only if the triangle is acute (i.e. does not have an angle greater than or equal to a right angle). If one angle is a right angle, the orthocenter coincides with the vertex at the right angle.[2]
Cary, North Carolina Raleigh, Durham, and Chapel Hill make up the three primary metropolitan areas of the Research Triangle metropolitan region. The regional nickname of "The Triangle" originated after the 1959 creation of the Research Triangle Park, primarily located in Durham County, four miles from downtown Durham. RTP is bordered on three sides by the city of Durham and is roughly midway between the cities of Raleigh and Chapel Hill, and the three major research universities of NC State University, Duke University, and University of North Carolina-Chapel Hill.