the answer is d and now pls  help me pls 
 
        
                    
             
        
        
        
answer:
set 4
Step-by-step explanation:
because when you divide the numbers 12,16 and 20 by 2 you'll get 6,8 and 10 which is a Pythagoras family....and it will form a right angle triangle 
 
        
             
        
        
        
c is the correct answer of this question 
 
        
                    
             
        
        
        
Slope intercept form = Y = Mx + B
15 = -3y + 21x
3y = 21x - 15
Y = 21/3 X - 15/3
Y = 7x - 5 = SI Form
        
             
        
        
        
Answer:
-  -1
-  0
Step-by-step explanation:
1. cos(π) = -1
2. sin(π) = 0
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It is useful to memorize the table below.