 Hello and welcome to the session. My name is Mansi and I'm going to help you with the following question. The question says in triangle ABC, AD is the perpendicular bisector of BC. C figure 7.30. Here we have to show that triangle ABC is an isosceles triangle in which AB equals to AC. So in the question it's given to us that AD is the perpendicular bisector of BC. That means AD stands perpendicular on BC and it divides BC into two equal halves, that is, BD is equal to DC. So let us see the solution to this question in triangle ABD and triangle ACD VD is equal to CD because AD is the perpendicular bisector of BC because AD is the perpendicular bisector of BC. Next we see that angle VDA is equal to angle CDA that is equal to 90 degree because AD is perpendicular on BC and also we see that AD is the common site so we say that AD is common. Now by these three things we have triangle ABD is congruent to triangle ACD by SAS congruence rule that means side angle site. So AB is also equal to AC by CPCT that is congruent parts of congruent triangles hence proved. So I hope you understood the question and enjoyed the session. Have a good day.