Given : XM || AB, XN || AC
To Prove : TX2 = TB × TC
Proof: ∵ BN || XM
Now, in ∆TXM, we have
BN || XM.
Therefore, by using Basic proportionality theorem, we have
...(i)
And,
Now, In ∆TMC, we have
∵ XN || CM
Therefore, By using Basic proportionality theorem, we have
Comparing (i) and (ii), we have