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Orthocenter of a triangle

Recall that 3 or more lines are said to be concurrent if and only if they intersect at exactly 1 point. The ORTHOCENTER of a triangle is the point of concurrency of the LINES THAT CONTAIN the triangle's 3 ALTITUDES. In the applet below, point O is the orthocenter of the triangle. Move the white vertices of the triangle around and then use your observations to answer the questions below the applet.

Is it ever possible for a triangle's orthocenter to lie OUTSIDE the triangle? If so, under what circumstance(s) will this occur?

Is it ever possible for a triangle's orthocenter to lie ON THE TRIANGLE ITSELF? If so, under what circumstance(s) will this occur? And where on the triangle will it lie?

Is it ever possible for a triangle's orthocenter to lie INSIDE the triangle? If so, under what circumstance(s) will this occur?