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In \(△ABC\), right-angled at \(C\), let \(X\) be the midpoint of the hypotenuse \(AB\). A line is drawn through \(X\), parallel to side \(BC\), meeting \(AC\) at \(D\). Prove the required result
 
Show that
 
(i) \(D\) is the mid-point of \(AC\)
 
(ii) \(MD ⊥ AC\)
 
(iii) \(CM = MA = \frac{1}{2}AB\)
 
Proof
 
(i) To Prove: \(D\) is the mid-point of \(AC\)
 
 
session 7 question 8 IMAGE6.png
 
Now, from \(∆ABC\) we can see \(X\) is the mid point of side \(AB\) and
 
\(DX || BC\)   [Given]
 
The by Mid-point theorem, 'The line drawn through the mid-point of one side of a triangle, parallel to another side bisects the third side.'
 
Therefore, \(DC=\)
 
Hence, \(D\) is the mid-point of AC.
 
 
(ii) To Prove: \(XD ⊥ AC\)
 
Proof:
 
As we know \(XD || BC\) and \(AC\) is transversal
 
This implies, \(∠ACB = ∠ADX = ^°\)
 
Hence, \(XD ⊥AC\)
 
 
(i) To Prove: \(CX = AX = \frac{1}{2}AB\).
 
Proof:
 
Considering \(∆ADX\) and \(∆CDX\)
 
\(AD = \)  [\(D\) is the mid point of \(AC\) ]
 
\(∠CDX = ∠\) (\(MD ⊥AC\))
 
\(DX = \) ()
 
\(∆ADX ≅ ∆CDX\) (By )
 
\(CX = \)  (By )
 
\(CX = AX= \frac{1}{2} AB\) (X is the mid point of AB)