The tangent to x2+y2=9 which is parallel to y-axis and does not lie in the third quadrant touches the circle at the point

The equation of a tangent parallel to y-axis is x = c.This touches x2+y2=9. Therefore, c=±3.Thus, the equations of the tangents are x=±3.Clearly, x = 3 is the tangent not lying in the third quadrant and it meets the circle at (3, 0).