A circle with centre (2,-1) have a tangent 3x+y=0.Find the equation of the other tangent which passes through the origion??
assume the circle in the general form then center is given, substitute values of -g ,-f then xx1 + yy1 + 2gx + 2fy +c = 0 , represents a tangent at (x1,y1) but 3x + y =0 compare coefficients. proceed to get the circles eqn then find thr reqd, tangent !
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