 Hello friends, welcome to the session I am Malka. Let's discuss a given question. State which pairs of triangles in figures 6.34 are similar. Write the similarity criteria used by you for answering the question and also write the pairs of similar triangles in the symbolic form. We are given with two triangles triangle DEF and triangle PQR. In the triangle DEF, angle D is 70 degree and angle E is 80 degree. And in triangle PQR, angle Q is 80 degree and angle R is 30 degree. Now let's start with the solution. First of all we will consider the triangle DEF. In triangle D, we will apply angle sum property. That is the sum of the angles of the triangle is equal to 180 degree. So 70 degree plus 80 degree plus angle F equal to 180 degree. This is by angle sum property. Therefore we get angle F equal to 30 degree. Now we will consider the triangle PQR. In triangle PQR, we see that 80 degree plus 30 degree plus angle P is equal to 180 degree. That is again by angle sum property. So from this we get this implies angle P is equal to 70 degree. From this we see that angle D is equal to angle P is equal to 70 degree and is equal to angle Q is equal to 80 degree. Angle F is equal to angle R is equal to 30 degree. So from this we conclude that the triangle DEF is similar to triangle PQR by AA criteria of similarity. Therefore we can say that yes the two triangles are similar by AA criteria of similarity. So this can be written as that triangle DEF is similar to triangle PQR. So hope you understood it and enjoyed it. Keep smiling and take care.