Q20 of 50 Page 1

Find the ratio in which the line segment joining the points A (3, -3) and B (-2, 7) is divided by x-axis. Also find the coordinates of the point of division.

Given A (3, -3) and B (-2, 7)


Let the ratio be k: 1.


We know that the section formula is as follows:



Thus, the coordinates of the point which divides AB in the ratio 1: k are


This point lies on the x-axis, and we know that on the x- axis, y-coordinate is 0.


⇒


⇒ 7k – 3 = 0


⇒ 7k = 3


⇒ k = 3/7


The ratio is 3/7: 1


Putting the value of k = 3/7, we get the point of intersection as


∴ The required ratio is 3/7: 1 and the coordinates of the point of division are (3/2, 0).


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