Using the vertex of the quadratic function, it is found that:
a) The maximum number of customers in the store is at 12 P.M.
b) 75 customers are in the store at this time.
The number of customers in x hours after 7 AM is given by:
[tex]y = -x^2 + 10x + 50[/tex]
Which is a quadratic equation with coefficients [tex]a = -1, b = 10, c = 50[/tex]
Item a:
The maximum value, considering that a < 0, happens at:
[tex]x_v = -\frac{b}{2a}[/tex]
Hence:
[tex]x_v = -\frac{10}{2(-1)} = 5[/tex]
5 hours after 7 A.M, hence, the maximum number of customers in the store is at 12 P.M.
Item b:
The value is y(5), hence:
[tex]y(5) = -(5)^2 + 10(5) + 50 = 75[/tex]
75 customers are in the store at this time.
A similar problem is given at https://brainly.com/question/24713268