Question

Ncert ch-7 ex 7.2 question 5 class 10

Answer 1

Given: The question is: Find the ratio in which line segment joining A (1, -5) and B(-4,5) is divided by x axis.

To find: The ratio, the coordinates of the point of division.

Solution:

• Now we have given the points A (1, -5) and B(-4,5).

• Lets assume that the point is C which divides line AB.

• Let the ratio be k : 1

• Now we know the section formula:

              mx2 + nx1/ m+n, my2 + ny1/ m+n

• Since its divided by y axis so:

              y = my2 + ny1/ m+n

              0 = (-5)(1) + 5k / k+1

              -5 + 5k = 0

              5k = 5

              k = 1

• So the ratio is 1:1

• Now, x-coordinate will be:

              x = mx2 + nx1/ m+n

              x = 1(1) + (-4)(1) / 1+1

              x = 1 - 4/ 2

              x = -3/2

Answer:

     So the ratio is 1:1 and the point which divides the line AB is (-3/2 , 0)