there is an equation for straight lines which goes
y-y,=m(x-x,)
where( x, , y, ) is any coordinate on the line and m is the gradient
so your answer is 
y-7= -2(x-4)
does this make sense?
 
        
                    
             
        
        
        
You need to put the Answers and picture/problem before asking someone to answer it.
        
             
        
        
        
Answer:1 2 and 4
Step-by-step explanation:
I just did it
 
        
                    
             
        
        
        
Answer: Barter
Step-by-step explanation: hope this helps
 
        
                    
             
        
        
        
(-4,-5)(-4,6)(3,8) 
all y signs become opposite!:)