JEE Main 2021 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 3 August 2021, Shift 1, Maths Q72

Question 72 of 90 in this shift, Maths question 12 of 30, Section A.

The sum of the values of 'a' for which circles of radius

\frac{\sqrt{5}}{3}

, touch the straight lines,

x - 2y - a = 0

and

3x - 6y + 7 = 0

, is

(1) $\frac{14}{3}$
(2) $-\frac{20}{3}$
(3) $\frac{10}{3}$
(4) $-\frac{14}{3}$ Official answer

Official answer

Option 4

NTA final key.

Chapter: Straight Lines
Topic: Straight Line Distance
Idea tested: Distance between parallel lines

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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.