For the vertex of △ ABC, find (1) the coordinate of the center of gravity of △ ABC, (2) the linear equation of the area of △ ABC through point a

Let the three vertex coordinates of △ ABC be a (x1, Y1), B (X2, Y2), C (X3, Y3) 1. The center of gravity of the triangle is the intersection of the three midlines, whose coordinates are ((x1 + x2 + x3) / 3, (Y1 + Y2 + Y3) / 3) 2) passing through point A. let the straight line of the area of △ ABC pass through the center of BC: ((x2 + x3) / 2, (Y2 + Y3) / 2) the equation is x-x1 = (Y-Y2

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