Three Dimensional Geometry Question 340
Question: The ratio in which the line joining (2, 4, 5), (3, 5,- 4) is divided by the yz plane, is
Options:
A) 2 : 3
B) 3 : 2
C) -2 : 3
D) 4 : - 3
Show Answer
Answer:
Correct Answer: A
Solution:
[a] Let the point R divides the line joining the points P(2, 4, 5) and Q(3, 5, -4) in the ration m:n.
$ \therefore $ The coordinate of R is $ ( \frac{3m-2n}{m+n},\frac{5m-4n}{m+n},\frac{-4m+5n}{m+n} ) $ Since, the point R is on yz-plane, therefore x-coordinate will be zero.
$ \therefore \frac{3m-2n}{m+n}=0\Rightarrow 3m-2n=0\Rightarrow 3m=2n $
$ \Rightarrow \frac{m}{n}=\frac{2}{3} $
BETA
