Answer: 
Step-by-step explanation:
Slope of a line passes through (a,b) and (c,d) = 
In graph(below) given line is passing through (-2,-4) and (2,2) .
Slope of the given line passing through (-2,-4) and (2,2) =
Since parallel lines have equal slope . That means slope of the required line would be .
Equation of a line passing through (a,b) and has slope m is given by :_
(y-b)=m(x-a)
Then, Equation of a line passing through(-3, 1) and has slope =  is given by

Required equation: 
 
        
             
        
        
        
The answer is that y is equal to zero
        
             
        
        
        
The set is not closed
Example:
-4 * -3 = 12  this is not a negative integer
 
        
             
        
        
        
Answer:
Step-by-step explanation:
1. 30 degrees (vertical angles)
2. 60 degrees (complementary angles)
3. 150 degrees (supplementary angles and vertical angles)
4. 90 degrees (complementary angles)