Question

an orthocenter is the intersection of three
angle bisectors in a triangle.
altitudes in a triangle.
medians in a triangle.
perpendicular bisectors in a triangle.

Explanation:

The orthocenter of a triangle is defined as the point where the three altitudes (perpendicular lines from each vertex to the opposite side) of the triangle intersect. The other options correspond to different triangle centers: angle bisectors meet at the incenter, medians meet at the centroid, and perpendicular bisectors meet at the circumcenter.

Answer:

altitudes in a triangle.