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) = 
Answer:
12 pencils in each package.
Step-by-step explanation:
Given:
Ethan bought 4 packages of pencils.
No of Packages = 4
No of pencils given to friend = 8 pencils
No of pencils left over =40 pencils
∴Total Number of Pencils = No of pencils given to friend + No of pencils left over =
Total Number of pencils in each package = 
<span><u><em>First way:</em></u>
The easiest and simplest way is to <u>count by 1</u> starting from 82 till you reach 512.
<u>This will go as follows:</u>
82, 83, 84, 85, ........... , 510, 511, 512
<u><em>Second way:</em></u>
We can note that the two given numbers are even numbers. This means that the two numbers are divisible by 2.
Therefore, we can <u>count by 2</u> starting from 82 till we reach 512.
<u>This will go as follows:</u>
82, 84, 86, 88, ................... , 508, 510, 512
<u><em>Third way:</em></u>
We can note that the units digit in both numbers is the same (the digit is 2). This means that we can count from 82 till 512 by <u>adding 10 each time</u>.
<u>This will go as follows:</u>
82, 92, 102, 112, ......................, 492, 502, 512
Hope this helps :)</span>
1 journal = 280 grams
3 journals = 280 * 3
280 * 3 = 840
Total weight of 3 journals = 840 grams
