Questions in circle

Select	Question
	If a circle, whose centre is (–1, 1) touches the straight line $x+2y+12=0$ , then the coordinates of the point of contact are
	If the tangent at a point $P(x,y)$ of a curve is perpendicular to the line that joins origin with the point P, then the curve is
	The slope of the tangent at the point $(h,h)$ of the circle ${{x}^{2}}+{{y}^{2}}={{a}^{2}}$ is
	If the straight line $4x+3y+\lambda =0$ touches the circle $2({{x}^{2}}+{{y}^{2}})=5$ , then $\lambda $ is
	The gradient of the normal at the point (–2, –3) on the circle ${{x}^{2}}+{{y}^{2}}+2x+4y+3=0$ is
	Equation of the tangent to the circle ${{x}^{2}}+{{y}^{2}}={{a}^{2}}$ which is perpendicular to the straight line $y=mx+c$ is
	A circle with centre (a, b) passes through the origin. The equation of the tangent to the circle at the origin is
	The two circles ${{x}^{2}}+{{y}^{2}}-2x+6y+6=0$ and ${{x}^{2}}+{{y}^{2}}-5x+6y+15=0$ touch each other. The equation of their common tangent is
	The length of the tangent from the point (4, 5)to the circle ${{x}^{2}}+{{y}^{2}}+2x-6y=6$ is
	The equation to the tangents to the circle ${{x}^{2}}+{{y}^{2}}=4$ , which are parallel to $x+2y+3=0$ , are