Alex is making a square with 4 corners, brittanie is making a triangle with 3 corners. That's the difference, hope it helped a little, it's not a full answer but maybe it will help.
        
             
        
        
        
Answer:
y=0.8x
Step-by-step explanation:
take two points from the graph
(5,4) and (0,0)
then do y2-y1/x2-x1
4-0/5-0
4/5=.8
 
        
             
        
        
        
Answer:
I'm pretty sure it is 50n+200 <u><</u> 3600
Step-by-step explanation:
Im to fully sure tho
 
        
             
        
        
        
1/2 X base X height= triangle 
length X width X height= square