Section Formula :
Derive an expression for the co-ordinates of a point that divides the line joining points p(x1, y1, g1) and Q(x2, y2, g2) internally in the ratio m:n
Let P(x1, y1, g1) abd Q(x2, y2, g2) be the two points. Let the point R(x,y,g) divide PQ internally in the ratio m:n.
Draw PL, RN, and QM. PL || RN || QM.
Through the point R draw a line ST || LM, line ST will intersect the line LP externally at the point S and the line MQ at T.