In the adjacent figure, which lines are tangents to the circle ?

In adjacent figure, /_B

In the figure, which circles are congruent to the circle A?

In the adjacent figure O is the centre of the circle. If angle OAB=30^(@), angle ABC=120^(@), angle BCO=y^(@) and angle COA=x^(@) , then the find value sof x and y.

A circle is drawn in a sector of a larger circle of radius r, as shown in the adjacent figure. The smaller circle is tangent to the two bounding radii and the are of the sector. The radius of the small circle is-

In the adjacent figure, there are two concentric circles with centre ‘O’. Chord AD of the bigger circle intersects the smaller circle at B and C. Show that AB = CD.

In the adjacent figure, AB be diameter of a circle whose centre is O. If angleAOE = 150^@ , angleDAO =51^@ then the measure of angleCBE is___

The radii of two concentric circles are 5 cm and 3 cm respectively . Find the length of the chord of the greater circle which is also a tangent to the smaller circle.

AB is a diameter of a circle. BP is a tangent to the circle at B . A straight line passing through A intersects BP at C and the circle at D . Prove that BC^(2)=ACxxCD .

In the adjacent figure, bar(AB) is a straight line. Find the value of x and also find angleAOC, angleCOD and angleBOD .

In the adjacent figure lines PQ and RS intersect each other at point O. If anglePOR : angleROQ = 5: 7, find all the angles.