Question

In the figure 10.12, if angle BAO= angle DCO and OC=OD, show that AB||CD.

Answer 1

Given: angle BAO = angle DCO and OC = OD

To find: Show that AB||CD.

Solution:

• Now we have given that angle BAO = angle DCO and OC = OD.

• In triangle ODC, we have:

              angle ODC = angle OCD .........(i)  .....(angles of isosceles triangles )

• But we have given that :

              angle DCO = angle BAO ............(ii)

• So fron (i) and (ii), we get:

              angle ODC = angle BAO

• So these are alternate interior angles, so:

              AB || CD

Answer:

           So we proved that AB || CD .

Answer 2

Hence it is proved that AB || CD