Answer:

Step-by-step explanation:
we know that

Remember the identity

step 1
Find the value of 
we have that
The angle alpha lie on the III Quadrant
so
The values of sine and cosine are negative

Find the value of sine

substitute




step 2
Find the value of 
we have that
The angle beta lie on the IV Quadrant
so
The value of the cosine is positive and the value of the sine is negative

Find the value of cosine

substitute




step 3
Find cos (α + β)

we have




substitute



The answer is 1.5 or 1 1/2.
here is the how you get this answer.
1: Cross Multiply (1.2)(60)=x
2: divide x by 48
3: you should get 1.5 or 3/2
BTW x is equal to 72
A book is sold in Belize for 80.39 Belize dollars.
In Brazil, it sells for 63.65 Brazilian reals.
The exchange rate of US Dollars to Belize Dollars is 1:1.9246
<span>The exchange rate of US Dollars to Brazilian Real is 1:1.7880
</span>
If we convert the two into dollars,
Belize Dollars
1 : 1.9246 = X : <span>80.39
1.9246X = 80.39
X = $ 41.77
</span>Brazilian Real
1 : 1.7880 = X : 63.65 <span>
</span>1.7880X = 63.65 <span>
X = $ 35.60
</span>
Difference = $ 41.77 - $ 35.60
Difference = $ 6.17
<span>So, in Belize the book is more expensive by $ 6.17</span>