Prove that if a rectangle is inscribed in a circle, then the point of intersection of its diagonals must lie at the centre of the circle.
 
Explanation:
 
YCIND_240403_6137_Circles_18.png
 
Given, \(ABCD\) is a rectangle inscribed in a circle.
 
Let the diagonals \(AC\) and \(BD\) intersect at the point \(O\).
 
\(OA=\) and \(OB =\) []
 
This implies, \(O\) is the .
 
Also, we know that, every angle in a rectangle is \(^\circ\).
 
Since, the rectangle is inscribed in a circle, the diagonals \(AC\) and \(BD\) are the of the circle.
 
So, the chords \(AC\) and \(BD\) subtends a at the circumference.
 
Thus, the diagonals \(AC\) and \(BD\) are the of the circle. [Since, ]
 
Therefore, the point \(O\) is the of the circle.
 
Therefore, the diagonals of the rectangle \(ABCD\) intersect at the centre.