If the straight line passing through m is the vertex corresponding to this side, we can use the principle of equal area with the same base, as long as m is the midpoint of any side. Make a circle with the two endpoints of one side as the center. The radius of the circle is greater than the length of the side, and then you will get two intersections. After connecting the intersection points, the intersection point with an edge is the midpoint of this edge. Connect the midpoint and the opposite vertex, and the two triangles have equal areas.