In which type of triangle is the orthocenter on the perimeter of the triangle

The triangle in which the orthocenter lie on the perimeter of the triangle is:

                    Right Triangle.

Orthocenter of a triangle--

The orthocenter of a triangle is a point where the three altitudes of a triangle intersect.

As we know that in a right angled triangle each leg of the triangle act as an altitude.

Hence, in a right triangle the vertex containing the right angle will behave as the orthocenter of the triangle and hence lie on the perimeter of the triangle.

              Hence, the answer is:

                  Right triangle.