Question 622349
  <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi,  
Re: TY  Note: Graph demonstrates Profit Peaks at ~16 tiles and then decreases as more tiles are sold
Careful, the (-1) stays in effect 
P(x)= (-1)x^2 + 33x - 20
P(20)= (-1)20^2+(33*20)-200
P(20)= -400+660-200 = 60
P(25)= (-1)25^2+(33*25)-200
 P(25)= - 625+825-200 = 0
{{{drawing(300,300,   -10,50,-10,100, grid(1),
circle(25, 0,0.8),
circle(20, 60,0.8),
circle(16.5, 72.25,0.8),
graph( 300, 300, -10,50,-10,100,0,(-1)x^2 + 33x - 200 ))}}}