Answer:
c
Step-by-step explanation:
 
        
             
        
        
        
The answer: x is equal to 50
        
                    
             
        
        
        
So now its

but you want it in y=mx+b so 
add x to both sides so that you have y on its own 
so now it's 
 
 
        
        
        
17. 9
18. 12
19. 16
20. 56
21. 143
22. 14
23. 27
24. 7
        
             
        
        
        
Answer:
Start at -150, then add 3(-5), then add 122.2. -150 + 3(-5) + 122.2 = -45.3.