Today I am solving the ncert class 9th solution of chapter triangles.Find the best solution of exercise 7.2 question number 5, also find the simplest and easiest solution of this question. Also find the best solution of this question in a simple method. ABC and DBC are two isosceles triangles on the same base BC (see Fig. 7.33). Show that ABD = ACD.
In the question, it is given that ABC and DBC are two isosceles triangles.
We will have to show that ABD = ACD
Proof:
Triangles ΔABD and ΔACD are similar by SSS congruency since
AD = AD (It is the common arm)
AB = AC (Since ABC is an isosceles triangle)
BD = CD (Since BCD is an isosceles triangle)
So, ΔABD ΔACD.
∴ ABD = ACD by CPCT.