Question

In the given figure a straight line L passing through the circle O bisects the chord AB and CD prove that AB||CD

Answer 1

we know that perpendicular from centere bisects the chord. Let there be two chords AB and CD. A line MOL with bisects these chords.

Therefore, om must be perpendicular to AB and OL to CD.

Now, angle OMB = angle OLD = 90

These are co int angles and are supplimentry. I.E angle OMB + angle OLD = 90 +90 = 180

Corrensponding angles are supplementry thus the two chords are parallel