Let's start by understanding the scenario. First, you have …

Let's start by understanding the scenario. First, you have an equilateral triangle with all sides equal to 6 cm. By dropping a perpendicular from the top vertex to the midpoint of the base, you split the equilateral triangle into two congruent right triangles. In each of these right triangles, the hypotenuse is 6 cm, and the base is half of 6 cm, which is 3 cm.