\(P\) is a point on the side \(BC\) of \(\Delta ABC\) such that \(\angle APC = \angle BAC\). Prove that \(AC^2 = BC \cdot CP\). 
 
 Proof:
 
Given a triangle \(ABC\) with a point \(P\) on \(BC\) such that \(\angle APC = \angle BAC\). 
 
\(AC^2 = BC \cdot CP\) 
 
Since \(\angle APC = \angle\)
 
By similarity criterion, \(\Delta APC \sim \Delta\)
 
Since they have one    and \(\angle APC = \angle BAC\). 
 
For similar triangles, the ratio of corresponding sides are equal. 
 
\(\frac{AC}{BC} =\)ii

\(AC^2 = BC \cdot PC\) 
 
Hence proved.