Answer:
A.16–i is correct. 
Step-by-step explanation:
(4+i)(4–i). [(a+b)(a–b)=(a²–b²)]
(4²–i²)=16–i
I hope this answer is correct so please vote my answer
 
        
             
        
        
        
Answer:
Step-by-step explanation:
I will help u if you help me????
 
        
             
        
        
        
Step-by-step explanation:
The number of subsets=2ⁿ where n=4 members
2ⁿ=2⁴=16
Number of proper subsets=2ⁿ-1
16-1=15
 
        
             
        
        
        
The question said that it told you the base angles. A roof would have two equal base angles. The base angles= 53
All the angles of a triangle each 180, (the roof is shaped like a triangle) 
So, let's make x the missing angle.
53(2)+x=180
106+x=180
Subtract 106 on both sides. 
180-106= 74
The vertex angle is 74. 
I hope this helps!
~cupcake