Lines that contain the altitudes of a triangle?

The altitudes of a triangle are the segments drawn from each vertex perpendicular to the opposite side. These lines intersect at a point called the orthocenter, which can lie inside the triangle for acute triangles, on the vertex for right triangles, and outside for obtuse triangles. Each altitude represents the height of the triangle from that vertex, contributing to the calculation of the triangle's area. The altitudes can be constructed using geometric methods or calculated using coordinate geometry.