question_answer

    In figure,  and  Prove that OR In figure,  bisects  and  Prove that  

Answer:

    Since, AD BC and AB is the transversal                           ...(i) (1) [coinheritor angle] Similarly, since  andis the transversal [coinheritor angles] ...(ii) (1) From Eqs. (i) and (ii), we get                  (1)                           OR Inwe have exterior  [exterior angle of a triangle is equal to the sum of two interior opposite angles]            (1)  exterior (given)           exterior is bisected by                                                     (1) But these are alternate interior angles formed when, the transversal AC cuts the line AE and BC.                                                              (1) Hence proved.