Question 368302
{{{T(x)= -0.4x^2+20x+122.1}}}
Just substitute for x with the number of days.
I'll do one you do the rest.
For {{{x=10}}},
{{{T(10)= -0.4(10)^2+20(10)+122.1}}}
{{{T(10)= -0.4(100)+200+122.1}}}
{{{T(10)= -40+222.1}}}
{{{T(10)=182.1}}}
Since you can't sell 0.1 of a ticket, on the 10th day, 182 tickets were sold.
Follow the same process for {{{x=20}}}, {{{x=40}}}, and {{{x=50}}}.