I think you set up the equation like this 
$2.50x+5
I hope I helped sorry if I didn't.
        
             
        
        
        
The equation of a line which has the slope m and passes through the point A(x1,y1) has the formula:
y-y1=m(x-x1)
in your case m= -5 ; A(x1;y1)=(1;-1)
y-(-1)= -5(x-1)
y+1= -5(x-1)
answer is c 
        
                    
             
        
        
        
B) Detergent B is less expensive than Detergent A 
        
                    
             
        
        
        
 We can use the distributive property for this:
4 (p+2) = 28
4p + 8 = 28.
4p = 28 - 8.
4p = 24.
Divide by 4 on both sides:
p = 6
 
        
             
        
        
        
The correct answer would be 6.
To figure this out, you take the square root of 36 since area of a square is side x side.