Questions in circle

Select	Question
	The equations of the tangents to the circle ${{x}^{2}}+{{y}^{2}}={{a}^{2}}$ parallel to the line $\sqrt{3}x+y+3=0$ are
	The angle between the tangents to the circle ${{x}^{2}}+{{y}^{2}}=169$ at the points (5, 12) and (12, –5), is
	If the line $x=k$ touches the circle ${{x}^{2}}+{{y}^{2}}=9$ , then the value of $k$ is
	If the line y $\cos \alpha =x\sin \alpha +a\cos \alpha $ be a tangent to the circle ${{x}^{2}}+{{y}^{2}}={{a}^{2}}$ , then
	Circle ${{x}^{2}}+{{y}^{2}}-4x-8y-5=0$ will intersect the line $3x-4y=m$ in two distinct points, if
	The two tangents to a circle from an external point are always
	The area of the triangle formed by the tangents from the points (h, k) to the circle ${{x}^{2}}+{{y}^{2}}={{a}^{2}}$ and the line joining their points of contact is
	If the equation of one tangent to the circle with centre at (2, –1) from the origin is $3x+y=0$ , then the equation of the other tangent through the origin is
	The equations of the normals to the circle ${{x}^{2}}+{{y}^{2}}-8x-2y+12=0$ at the points whose ordinate is –1, will be
	If the ratio of the lengths of tangents drawn from the point $(f,g)$ to the given circle ${{x}^{2}}+{{y}^{2}}=6$ and ${{x}^{2}}+{{y}^{2}}+3x+3y=0$ be 2 : 1, then