记△ABC中x边上的中点为Gx,x∈{a,b,c}(a≥b≥c),Fx为a、b、c三边中除x边外的另两边所成折线长的中点.称Fx为相对于x边的折中点,线段FxGx为x边的折中线.文[1]证明了三角形的三条折中线共点(此点称为三角形的折心)以及折心的一些性质,且文[1]末提出了如下问题　设Fx是△ABC的折 Remember that the midpoint on the x-side of △ABC is Gx, x∈{a,b,c} (a≥b≥c), where Fx is the polyline formed by the other two sides except x in the three sides a, b, and c. The long midpoint. Let Fx be the midpoint relative to the x-edge. The line segment FxGx is the midline of the x-edge. The paper [1] proves that the triangle has three points in the centerline (this point is called the triangle’s fold center) and Some properties of the center of gravity, and at the end of [1], the following questions were asked: Let Fx be △ABC