Answer:
[tex]Max = 15[/tex]
Step-by-step explanation:
Given
[tex]s(y) = -2y^2 + 60y + 10[/tex]
Required
Determine number of items that gives maximum earnings;
The general form of a quadratic equation is:
[tex]s(y) = ay^2 + by + c[/tex]
And the maximum is calculated as:
[tex]Max = \frac{-b}{2a}[/tex] If a<0
Comparing [tex]s(y) = ay^2 + by + c[/tex] to [tex]s(y) = -2y^2 + 60y + 10[/tex]
We have that:
[tex]a = -2[/tex] [tex]b = 60[/tex] [tex]c = 10[/tex]
Substitute these values to
[tex]Max = \frac{-b}{2a}[/tex]
[tex]Max = \frac{-60}{2 * -2}[/tex]
[tex]Max = \frac{-60}{-4}[/tex]
[tex]Max = 15[/tex]
The number of item that maximizes the function is when y = 15