If is both the altitude and median of then is ________.A.cannot determineB.obtuse scaleneC.isoscelesD.acute scalene

The answer is C. isosceles.

Here's the step-by-step explanation:

In a triangle, a line segment is called a median if it connects a vertex of the triangle to the midpoint of the opposite side. An altitude, on the other hand, is a line segment from a vertex of the triangle perpendicular to the line containing the opposite side.

If a line segment is both a median and an altitude, it means it is drawn from a vertex to the midpoint of the opposite side and is also perpendicular to the opposite side. This is only possible in an isosceles triangle, where two sides are of equal length and the angles opposite these sides are also equal.

In an isosceles triangle, the line drawn from the vertex angle (the angle opposite the base) to the midpoint of the base is both a median (since it bisects the base) and an altitude (since it forms right angles with the base). Therefore, if a line segment is both a median and an altitude of a triangle, the triangle must be isosceles.