Use geometry words to describe a way to separate triangles into other triangles

You can divide a triangle using medians. Let's name triangle ΔABC shown in figure 1. So you must start at one of the vertices and then bisect the opposite side. Let's start with the point A and then we bisect the opposite side. Then the length from B to D is equal to the length from D to C. So let's take the point B and then we bisect the opposite side. Then the length from A to E is equal to the length from E to C. The same reasoning happens with the point C. So we have, in figure 2, the triangle ΔABC divided into six triangles which all have the same area.

Maybe the answer is 20mm. all i really did was just multiply, which is obvious.