The circles `x^2+y^2-2x-4y+1=0`and `x^2+y^2+4x+4y-1=0`touch internallytouch externallyhave `3x+4y-1=0`as the common tangent at thepoint of contacthave `3x+4y+1=0`as the common tangent at thepoint of contactA. touch internallyB. touch externallyC. have `3x+4y-1=0` as the common tangent at the point of contactD. have `3x+4y+1=0` as the common tangent at the point of contanct.

The circles `x^2+y^2-2x-4y+1=0`and `x^2+y^2+4x+4y-1=0`touch internally

1.	The circles `x^2+y^2-2x-4y+1=0`and `x^2+y^2+4x+4y-1=0`touch internallytouch externallyhave `3x+4y-1=0`as the common tangent at thepoint of contacthave `3x+4y+1=0`as the common tangent at thepoint of contactA. touch internallyB. touch externallyC. have `3x+4y-1=0` as the common tangent at the point of contactD. have `3x+4y+1=0` as the common tangent at the point of contanct.
Answer» Correct Answer - 2,3 For the given circles `S_(1) : x^(2)+y^(2)-2x-4y+1=0` and `S_(2) : x^(2) + y^(2)+4x+4y-1=0` `C_(1) -= (1,2) r_(1)=2,C_(2) -= (-2,-2) , ` and `r_(2)=3` Now, `r_(1)+r_(2)=5` and `C_(1)C_(2)=5`. Hence, the circles touch externally. Also, the common tangent at the point of contact is `S_(1) - S_(2)=0` or `3x+4y-1=0`.

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