5
Consider the segment joining the points A(1,2) A(1,2) A(1,2) and B(2,−1) B(2,-1) B(2,−1). The equation of the line that divides this segment in the ratio a:b a:b a:b is given by: (b3a,−3)and(−3,−b3a). \left( \frac{b}{3a}, -3 \right) \quad \text{and} \quad \left( -3, \frac{-b}{3a} \right). (3ab,−3)and(−3,3a−b). Since the line divides the segment in the ratio p:q p:q p:q, this relationship holds.