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JEE MainMathematicsModerateCircles

What will be the equation of circle whose centre is (3,-1) and
which intercept chord of 6 unit length on straight line

2x−5y+18=02x - 5y + 18 = 0
ml o`Ùk dk lehdj.k ftl Unz (3, - 1) gS rFkk js[kk 2x - 5y + 18

= 0 ij 6 bdkbZ yEckbZ

Show answer and solution
AM=MB=3AM = MB = 3
CM=2(3)−5(−1)+1822+52=29CM = \frac{2(3) - 5( - 1) + 18}{\sqrt{2^{2} + 5^{2}}} = \sqrt{29}
⇒R2=CA2=AM2+CM2=32+29=38\Rightarrow R^{2} = CA^{2} = AM^{2} + CM^{2} = 3^{2} + 29 = 38
Equation of circle is o`Ùk dk lehdj.k

(x−3)2+(y+1)2=R2=38⇒x2+y2−6x+2y=28(x - 3)^{2} + (y + 1)^{2} = R^{2} = 38 \Rightarrow x^{2} + y^{2} - 6x + 2y = 28

Source: Grass-G / M-25 Mathematics Paper 7 Jan.docx

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