Answer:
x = ± 2i
Step-by-step explanation:
note that  = i
 = i
x² = - 12 ( take square root of both sides )
x = ±  = ±
 = ±  = ± 2i
 = ± 2i
 
        
             
        
        
        
3c(5+c) -2(3c-7)
15c+3c^2-6c+14
9c+3c^2+14
        
                    
             
        
        
        
w is the width and it is the independent variable. You can pick any positive whole number you want (within reason of course; you can't go to infinity or go beyond some set boundary). Whatever you picked for w, the expression 2w-5 will be dependent on it. So the length is dependent on the width.
For instance, if the width is w = 10 feet, then 2w-5 = 2*10-5 = 20-5 = 15 feet is the length. The choice of 10 feet for the width directly affects the length being 15 feet. 
 
        
             
        
        
        
9514 1404 393
Answer:
   arithmetic; common difference of 5
Step-by-step explanation:
It usually works well to check differences first. Here, they are ...
   8 -3 = 5
   13 -8 = 5
These are the same value, so the sequence is arithmetic with a common difference of 5.
 
        
             
        
        
        
Answer:
m = 1     c = -8
Step-by-step explanation: