JEE Main 2021 · MathsNumerical answerNumerical valueMediumMulti-step

JEE Main 3 August 2021, Shift 2, Maths Q86

Question 86 of 90 in this shift, Maths question 26 of 30, Section B.

The circles,

x^2 + y^2 + 2x + 4y - 4 = 0

and

x^2 + y^2 - 4x + 4y + k = 0

touch each other internally. If the point of contact of these circles is

(a, b)

, then

5(a^2 + b^2)

is equal to

\underline{\hspace{2em}}

Official answer

100

NTA final key.

Chapter: Conic Sections
Topic: Circle Tangents
Idea tested: Coordinates of Point of Contact

Same topic in other shifts

All Circle Tangents questions

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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.