JEE Main 2018MathematicsCircleMediumMCQ

JEE Main 2018 — Circle Question with Solution

JEE Main 2018 (15 Apr)

Question

A circle passes through the points 2,3 and 4,5. If its centre lies on the line y-4x+3=0, then its radius is equal to :

Choose an option

Show full solutionCorrect option: C
Correct answer
C2

Step-by-step explanation

Let centre of circle be Cα, β.

It lies in line y-4x+3-0⇒β=4α-3

∴ C α, 4α-3

∴CA=CB

By distance formula,

⇒α-22+4α-62=α-42+4α-82

⇒-4α+4-48α+36=-8α+16-64α+64

⇒64+8-4-48α=80-40

⇒α=4020=2

∴ C2,5

∴ r=2-22+5-32=2

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About this question

This is a previous-year question from JEE Main 2018, covering the Circle chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.