Question 371849
a) Correct!
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b)
{{{T(10)}} is incorrect.
{{{T(10)=-0.4(100)+20(10)+122.1}}}
{{{T(10)=200+122.1-40}}}
{{{T(10)= 282.1}}}
All of the other values are correct.
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c)Not sure what x=-5.5 and x=55.55 are??
The last day tickets will be sold is the last day that {{{T(x)>0}}}.
{{{T(55)=12.1}}}
{{{T(56)=-12.3}}}
{{{x=55}}}
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d) The quadratic function, {{{y=ax^2+bx+c}}}, has a maximum at {{{x=-b/2a}}}
{{{x=-20/(-0.8)=25}}}
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e){{{T(25)=372.1}}}
{{{T(25)=372}}}
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f) The maximum occurs at the vertex.
({{{25}}},{{{372.1}}})
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