Question 475786
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Hi,Previously posted
Using the vertex form of a parabola, {{{y=a(x-h)^2 +k}}} where(h,k) is the vertex
tickets = -.26x^2 + 13x + 35
tickets = -.26[x^2 - 50x]+ 35  |a = -.26 < 0 Parabola opens downward
tickets = -.26[x - 25)^2 - 625]+ 35
tickets = -.26(x - 25)^2 + 162.50 + 35
tickets = -.26(x - 25)^2 + 197.50  
Vertex is a maximum point. Ticket sales peak on the 25th day