Answer:
9x
Step-by-step explanation:
Since you are subtracting a negative from a positive you would get 9 
 
        
             
        
        
        
Answer:
I think that the equation would be Y= -2X^2-4X-4 .
Step-by-step explanation:
Hope it wad helpful :)
 
        
             
        
        
        
Answer:
2.5
Step-by-step explanation:
When a variable is next to a number (coefficient) it means you need to multiply. In this equation 6x are next to eachother. 
Because we don't know what x is, we have to work backwards. 
The opposite of multiplying is dividing, so here we can do...
15/6  and that equals 2.5 
To check you replace x with 2.5 like so,
6(2.5)= 15 and it is true!
Hope this helps and have a great day!
 
        
             
        
        
        
Answer:
157
Step-by-step explanation:
formula- 2 x 3.14 x 5 squared 
6.28 x 5 squared
6.28 x 25 
157