If a triangle has an obtuse angle, then its orthocenter is outside the triangle.
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True
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False
The orthocenter of a triangle is the intersection point of its three altitudes. In an obtuse triangle, the altitudes from the acute vertices lie outside the triangle, and their intersection point (the orthocenter) is indeed located outside the triangle. This is a well-known geometric property. The statement is true.
The orthocenter is the point where a triangle's three altitudes intersect. In an acute triangle it lies inside, in a right triangle it sits exactly at the right-angle vertex, and in an obtuse triangle the altitudes must be extended outside the triangle to meet, placing the orthocenter outside the triangle's boundary. This is a standard property taught alongside the circumcenter and centroid locations for different triangle types.