Answer: There are 
ways of doing this
Hi!
To solve this problem we can think in term of binary numbers. Let's start with an example:
n=5, A = {1, 2 ,3}, B = {4,5}
We can think of A as 11100, number 1 meaning "this element is in A" and number 0 meaning "this element is not in A"
And we can think of B as 00011.
Thinking like this, the empty set is 00000, and [n] =11111 (this is the case A=empty set, B=[n])
This representation is a 5 digit binary number. There are 
of these numbers. Each one of this is a possible selection of A and B. But there are repetitions: 11100 is the same selection as 00011. So we have to divide by two. The total number of ways of selecting A and B is the 
.
This can be easily generalized to n bits.
Answer:
C
Step-by-step explanation:
According to SohCahToa, cosine is adjacent over the hypotenuse.
The adjacent when looking from angle b, is 21.
The hypotenuse of this triangle is 29.
So Cos B=21/29
The answer for this problem is 1661
90°+b+b =180
90°+ 2b=180
2b=180-90
2b= 90
<u>2</u><u>b</u><u>=</u><u>9</u><u>0</u>
<u>2</u> = 2
b=45°
ave tried I don't know if its correct
Answer:
50
Step-by-step explanation:
Because of supplementary angles that line has to equal to 180
180-75 = 105
so 105 = (2x + 5)
you can subtract 5 from each side and get
100 = (2x)
then divide each side by 2 and you get
x = 50
you can check it by doing (2 x 50 + 5)
2 x 50 = 100 + 5 = 105 + 75 = 180
