The number of common tangents to the circles& | vedclass

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Question

$c_{1}(2,3);$

$r_{1}=\sqrt{4+9+12}=5$

And $c_{2}(-3,-9)$

$r_{2}=\sqrt{9+81-26}=8$

$	herefore \quad$ Distance $c_{1} c_{2}=\sqrt{25+144}=1

Vedclass · Accepted Answer

$3$

Vedclass · Answer

$c_{1}(2,3);$

$r_{1}=\sqrt{4+9+12}=5$

And $c_{2}(-3,-9)$

$r_{2}=\sqrt{9+81-26}=8$

$	herefore \quad$ Distance $c_{1} c_{2}=\sqrt{25+144}=13$

$	herefore \quad c_{1} c_{2}=r_{1}+r_{2}$ touching externally.

$\Rightarrow \quad 3$ common tangents.

The number of common tangents to the circles ${x^2} + {y^2} - 4x - 6y - 12 = 0$ and ${x^2} + {y^2} + 6x + 18y + 26 = 0$ is

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