CBSE|Drawing tangents from an external point to a circle

In figure, DE and DF are tangents from an external point D to a circle with centre A. If DE = 5 cm and DE_|_DF , then find the radius of the circle.

The number of tangents drawn from an external point to a circle is _____________.

Theorem: The length of two tangents drawn from an external point to a circle are equal.

The length of the tangent from an external point P to a circle of radius 5cm is 10cm . The distacne of the point from the centre of the circle is

In the figure, PA is a tangent from an external point P to a circle with centre O. If anglePOB = 115^(@) , find angleAPO .

What is the angle between the two tangents drawn from an external point to a circle and the angle subtended by the line-segment joining the points of the contact at the centre.

Prove that the angle between the two tangents drawn from an external point to a circle is supplementary to the angle subtended by the line segments joining the points of contact at the centre.

Prove that the angle between the two tangents drawn from an external point to a circle is supplementary to the angle subtended by the line-segment joining the points of contact at the centre.