xy plane divides the line joining the points \[\left( {2,4,5} \right)\] and $\left( { - 4,3, - 2} \right)$ in the ratio
A. $3:5$
B. $5:2$
C. $1:3$
D. $3:4$
Answer
299.7k+ views
Hint: In order to solve this type of question, first assume the ratio as k:1. Then, using the section formula i.e., $\left( {x,y,z} \right) = \left( {\dfrac{{{m_1}{x_2} + {m_2}{x_1}}}{{{m_1} + {m_2}}},\dfrac{{{m_1}{y_2} + {m_2}{y_1}}}{{{m_1} + {m_2}}},\dfrac{{{m_1}{z_2} + {m_2}{z_1}}}{{{m_1} + {m_2}}}} \right)$ we will find the required ratio. Here, $\left( {{x_1},{y_1},{z_1}} \right) = \left( {2,4,5} \right)$ and $\left( {{x_2},{y_2},{z_2}} \right) = \left( { - 4,3, - 2} \right)$. Also, ${m_1} = k$ and ${m_2} = 1.$
Formula used:
$\left( {x,y,z} \right) = \left( {\dfrac{{{m_1}{x_2} + {m_2}{x_1}}}{{{m_1} + {m_2}}},\dfrac{{{m_1}{y_2} + {m_2}{y_1}}}{{{m_1} + {m_2}}},\dfrac{{{m_1}{z_2} + {m_2}{z_1}}}{{{m_1} + {m_2}}}} \right)$
Complete step by step solution:
We are given that,
$A\left( {2,4,5} \right)$ and $B\left( { - 4,3, - 2} \right)$
Let xy plane divide the line joining the points in the ratio of $k:1.$
In the xy plane, z-coordinate must be $0.$
Solving for z-coordinate,
Using section formula, compare the z-coordinate to get the required ratio,
$ \Rightarrow \dfrac{{k\left( { - 2} \right) + 1\left( 5 \right)}}{{k + 1}} = 0$
$ - 2k + 5 = 0$
On solving,
$k = \dfrac{5}{2}$
$\therefore $The correct option is B.
Note: The line segment divides the xy plane, this means that the line joining the given points is parallel to z-axis. So, the z-coordinate is 0. Also, make sure that the coordinates of the point that divides the plane is $\left( {x,y,0} \right)$ and not $\left( {0,0,z} \right)$, otherwise it may lead to incorrect answer.
Formula used:
$\left( {x,y,z} \right) = \left( {\dfrac{{{m_1}{x_2} + {m_2}{x_1}}}{{{m_1} + {m_2}}},\dfrac{{{m_1}{y_2} + {m_2}{y_1}}}{{{m_1} + {m_2}}},\dfrac{{{m_1}{z_2} + {m_2}{z_1}}}{{{m_1} + {m_2}}}} \right)$
Complete step by step solution:
We are given that,
$A\left( {2,4,5} \right)$ and $B\left( { - 4,3, - 2} \right)$
Let xy plane divide the line joining the points in the ratio of $k:1.$
In the xy plane, z-coordinate must be $0.$
Solving for z-coordinate,
Using section formula, compare the z-coordinate to get the required ratio,
$ \Rightarrow \dfrac{{k\left( { - 2} \right) + 1\left( 5 \right)}}{{k + 1}} = 0$
$ - 2k + 5 = 0$
On solving,
$k = \dfrac{5}{2}$
$\therefore $The correct option is B.
Note: The line segment divides the xy plane, this means that the line joining the given points is parallel to z-axis. So, the z-coordinate is 0. Also, make sure that the coordinates of the point that divides the plane is $\left( {x,y,0} \right)$ and not $\left( {0,0,z} \right)$, otherwise it may lead to incorrect answer.
Recently Updated Pages
Letfx be a polynomial with positive degree satisfy-class-12-maths-JEE_Main

Evaluate the definite integral given as intlimits13left class 12 maths JEE_Main

The sum of squares of two parts of a number 100 is-class-12-maths-JEE_Main

Geometry of Complex Numbers Explained

JEE Main 2023 (February 1st Shift 2) Physics Question Paper with Answer Key

JEE Main 2023 (February 1st Shift 1) Maths Question Paper with Answer Key

Trending doubts
JEE Main 2026: Exam Dates, Session 2 Updates, City Slip, Admit Card & Latest News

Understanding the Electric Field of a Uniformly Charged Ring

Electron Gain Enthalpy and Electron Affinity Explained

Derivation of Equation of Trajectory Explained for Students

Understanding Atomic Structure for Beginners

How to Convert a Galvanometer into an Ammeter or Voltmeter

Other Pages
JEE Advanced Percentile vs Marks 2026: JEE Main Cutoff, AIR & IIT Admission Guide

Effective Nuclear Charge for JEE

What Are Current and Potential Difference in Electricity?

Hybridisation in Chemistry – Concept, Types & Applications

Isoelectronic Species: Definition, Examples & Importance

Understanding the Angle of Deviation in a Prism

