An isosceles triangle \(LMN\) is inscribed in a circle, with \(LM = LN\). Justify that the altitude from \(L\) to \(MN\) passes through the centre of the circle.
 
Proof:
 
Let the altitude from \(L\) meet \(MN\) at \(O\).
 
TBQ_2_3.PNG
 
Consider \(\Delta LOM\) and \(\Delta LON\).
 
The sides \(LM = LN\) []
 
\(LO = LO\) []
 
\(\angle LOM\) \(=\) \(LON\) \(=\) \(^{\circ}\) 
 
Therefore,  \(\Delta LOM ≅ \Delta LON\). [By ]
 
Thus, \(OM = ON\) [By ]
 
This implies that, \(O\) is the of the side \(MN\).
 
By the theorem:
 
Therefore, the altitude from \(L\) to \(MN\) passes through the centre of the circle.
 
Hence, proved.