Easy.png
Prove that for a square \(ABCD\), any line segment \(PQ\) that connects a point \(P\) on side \(AD\) to a point \(Q\) on side \(BC\) and passes through the center \(O\) of the square's diagonals. Prove that \(O\) divides \(PQ\) into two equal parts.
 
Given: \(ABCD\) is a square whose diagonals bisect each other at \(O\).
 
Proof
 
square 5th question - quadrilateral s3.png
 
In \(△ODP\) and \(△OBQ\) ,
 
\(∠BOQ=\)     [
]
 
\(∠OBQ=\)    [
] and
 
\(OB =\)         [
]
 
Therefore, \(△ODP≅△OBQ\)         [
]
 
Hence, \(OP=\)         [CPCT rule].
 
Therefore, Therefore \(O\) divides \(PQ\) into two equal parts
Answer variants:
ASA congruence rule
diagonals bisect each other
alternate interior angles
CPCT rule
Vertically oppsoite angles