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If the line lx+my+n=0 is tangent to the ...

If the line `lx+my+n=0` is tangent to the circle `x^(2)+y^(2)=a^(2)` , then find the condition.

Text Solution

Verified by Experts

The correct Answer is:
`a^(2)(l^(2)+m^(2))=n^(2)`
Distance of centre of the circle of the circle from the line must be radius of the circle.
`:. a= (|0+0+n|)/(sqrt(l^(2)+m^(2)))`
`:. a^(2)(l^(2)+m^(2))=n^(2)`
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