In the given figure, \(PQ||XZ\) and \(PR||XQ\), prove that \(\frac{YR}{RQ} = \frac{YQ}{QZ}\).
 
YCIND2402146037a16_2.png
 
Proof:
 
In \(\Delta XYZ\),
 
\(PQ ||\) i
 
If a line is drawn parallel to one side of a triangle to intersect the other two sides in distinct points, the other two sides are divided in the same ratio.
 
\(\frac{YQ}{QZ} =\) ii - - - - (1)
 
In \(\Delta XQY\),
 
\(PR ||\) i
 
If a line is drawn parallel to one side of a triangle to intersect the other two sides in distinct points, the other two sides are divided in the same ratio.
 
\(\frac{YR}{RQ} =\) ii - - - - (2)
 
From (1) and (2) we get,
 
iRQ=ii
 
Hence proved.