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) = 

I believe the answer is B. Hope this helps :)
Answer:
N+60
Step-by-step explanation:
The two equations are equivalent.
The postage for 3 posters is $5.
Lois$ wrote an expression for the total they both spent as 6x + 10 6(25) +10
150 +10 = 160
Clark wrote another expression for the total, saying that it represented the same cost: 2(3x + 5). = 2(3x) + 2(5) 6x + 10 = 6(25) + 10 = 150+10 160
If each poster costs $25, do the two expressions give the same amount?