If the tangent at 1, 7 to the curve x.x=Y - 6 touching the circle x.x+y.y+16x+12y+c=0 then the value of c is

find tangetto the parabola at (1,7)
it will come out as
y=2x+5

use distance from centre of the circle to the line as radiussince the line is tangent

and find out c

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