Y=-2x+8 
l hope that helps
        
             
        
        
        
T+11 because total would mean add them
        
                    
             
        
        
        
It would take 24 days for the patch to cover half of the lake
        
                    
             
        
        
        
Please, for clarity, use " ^ " to denote exponentiation:
Correct format: x^4*y*(4) = y*x^2*(13) 
This is an educated guess regarding what you meant to share. Please err on the side of using more parentheses ( ) to show which math operations are to be done first.
Your (x+y)2, better written as (x+y)^2, equals x^2 + 2xy + y^2, when expanded.
The question here is whether you can find this x^2 + 2xy + y^2 in your 
"X4y(4) = yx2(13)"
Please lend a hand here. If at all possible obtain an image of the original version of this problem and share it. That's the only way to ensure that your helpers won't have to guess what the problem actually looks like.
 
        
             
        
        
        
I know it is -1 cause of the root of equation