Correct answer is: distance from D to AB is 6cm
Solution:-
Let us assume E is the altitude drawn from D to AB.
Given that m∠ACB=120° and ABC is isosceles which means
m∠ABC=m∠BAC =
And AC= BC
Let AC=BC=x
Then from ΔACD , cos(∠ACD) =
Since DCB is a straight line m∠ACD+m∠ACB =180
m∠ACD = 180-m∠ACB = 60
Hence
Now let us consider ΔBDE, sin(∠DBE) =
