Question

maths questions pls help if u can step by step​

Answer 1

Answer:

In ∆ABC since AB = AC => angle ABC = angle ACB

Next we know for ∆ABC, angle DAC is exterior angle.

(here angle ACD = angle ADC)

angle DAC = angle ABC + angle ACB=2 angle ACB

Similarly, angle BAC = angle ADC + angle ACD = 2 angle ACD

since angle BAC + angle DAC = 180

=> 2angle ACB + 2 angle ACD=180

=> angle ACB + angle ACD = 90°

=> angle BCD = 90°