First find the midpoint of the opposing line from the vertex which your median is coming from. Use the equation x1+x2 /2 and y1+y2 /2 to find the midpoint. Next you need to find the slope of the same line. Use the equation y2-y1 / x2- x1 to find the slope. Then use the negative reciprocal of the line and the midpoint, to plot the median to the vertex.
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