The equation of tangent to the conic S≡ax2+by2+2hxy+2gx+2fy+c=0 at (x1 , y1) is obtained by replacing x with x+x12,y with y+y12,with x2 with xx1, y2 with yy1, xy with xy1+yx12 and keeping c as it is in the equation of conic (S).
True
This is a standard result we discussed in circle. We recommend you to remember the method. It is helpful while finding the equation of tangent to any second degree curve. In this method replace x with x+x12,
y→ y+y12
x2→ xx1
y2→ yy1
and
c→ c