To find the equation of tangents lines drawn from the point to the circle given by
Now to solve this example we follow these steps
Consider the given equation of circle
Compare this circle with general equation of circle as
Here we have following values
Now centre of the circle (i) is
Radius of circle (i) is
Let be the slope of the tangent drawn from to the given circle (i), then its equation is
Since the line (ii) is a tangent to the circle (i), so the distance of the centre of the circle should be equal to its radius, i.e.
Now solving this quadratic equation of variable , by quadratic formula, we have
Putting the value of one root, in equation (ii), we get
This is one equation of required tangents to the circle.
Putting the value of second root, in equation (ii), we get
This is second equation of required tangents to the circle.