JEE Main 2020 · MathsMultiple choiceSingle correctEasyCalculation

JEE Main 9 January 2020, Shift 2, Maths Q55

Question 55 of 75 in this shift, Maths question 5 of 25, Section A.

The following system of linear equations

7x+6y-2z=0

3x+4y+2z=0

x-2y-6z=0

, has

(1)no solution.
(2)only the trivial solution.
(3)infinitely many solutions, $(x,y,z)$ satisfying $y=2z$ .
(4)infinitely many solutions, $(x,y,z)$ satisfying $x=2z$ .Official answer

Official answer

Option 4

NTA final key (Jan 2020).

Chapter: Determinants
Topic: Cramer's Rule
Idea tested: Homogeneous System Solutions

Same idea in other shifts

Asked 4× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.