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Pleaseee helppp with thissss asapppp

Pleaseee helppp with thissss asapppp-example-1
User Mateusz Soltysik
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1 Answer

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6 votes

As we know that the standard equation of circle is
{\bf{(x-h)^(2)+(y-k)^(2)=r^(2)}} , where r is the radius of circle and centre at (h,k)

Now , as the circle passes through (2,9) so it must satisfy the above equation after putting the values of h and k respectively


{:\implies \quad \sf \{2-(-1)\}^(2)+(9-5)^(2)=r^(2)}


{:\implies \quad \sf (3)^(2)+(4)^(2)=r^(2)}


{:\implies \quad \sf 9+16=r^(2)}

After raising ½ power to both sides , we will get r = +5 , -5 , but as radius can never be -ve . So r = +5

Now , putting values in our standard equation ;


{:\implies \quad \sf \{x-(-1)\}^(2)+(y-5)^(2)=(5)^(2)}


{:\implies \quad \bf \therefore \quad \underline{\underline{(x+1)^(2)+(y-5)^(2)=25}}}

This is the required equation of Circle

Refer to the attachment as well !

Pleaseee helppp with thissss asapppp-example-1
User Anton Gildebrand
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2.7k points