CBSE Class 10 Answered

The equation of line joining the points (-1,3) and (9,8),

Y = MX + C  .....................where M = slope = 5/10 = 1/2

Y = X/2  + 7/2     ...........C, intercept at y-axis is found by using the point, (-1,3).

The coordinates of the point of division (a,b) will be the coordinates of intersection of these two lines,

2Y = X + 7 and x - y = -2

Hence,

2b = a + 7 and a - b = -2,

Solving these,

a = 3, b = 5.

Now, using section formula,

3 = (-n + 9m)/(m+n) or

3 = (-1 + 9m/n)/(m/n + 1)

3m/n + 3 = -1 + 9m/n

m/n = 4/6 = 2/3.

The division ratio will be 2:3

Regards,

Team,

TopperLearning.