Prove that the opposite sides of a quadrilateral circumscribing a
circle subtend supplementary angles at the centres of the circle.

Select and write the correct answer from the given alternatives in each of the following:An arc AB of a circle subtends an angle x radians at the centre O of the circle.Given that the area of the sector AOB is equal to the square of the length of the arc AB.then he value of x

Prove that, "If chords of congruent circles subtend equal angles at their centre, then the chords are equal."

Find the length of an arc of circle which subtends an angle of 108^@ at the centre, if the radius of the circle is 15cms.

Select and write the correct answer from the given alternatives in each of the following:The length of an arc of a circle which subtends an angle of 108^@ at the centre,if the radius of the circle is 15cm is

A circle passes through 3 vertices of a triangle. What is the centre of the circle called?

(0,0) is the centre of the circle passing through the vertices of an equilateral triangle. If the length of the median of the triangle is 9 units then equation of the circle is

Prove that any three points on a circle cannot be collinear.

A wire of length L carrying a current I is bent into a circle. The magnitude of the magnetic field at the centre of the circle is