Maybe you should work on starting you're sentences.
12 more boys than girls
ratio of boys to girls = 7:5
thus 2/12 is difference between boys and girls = 12
total students = 12 ÷ 2/12 = 72
The first box would be 2 and the second box would be 11.
49-65=2(3-11)
-16=2(-8)
-16= -16
Answer:

Step-by-step explanation:
To solve this problem you must know the formula of subtraction of angles for the function cosx.
The formula is:

We can write 30° as: 45° - 15°
Then:

Using the formula for subtraction of angles we have:

Notice that we have achieved the expression shown in the statement
Finally:
