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:

Which is a quadratic equation with coefficients 
Item a:
The maximum value, considering that a < 0, happens at:

Hence:

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:

75 customers are in the store at this time.
A similar problem is given at brainly.com/question/24713268
It would be A=18 because of the equation a^2+b^2=c^2.
The square's diagonal is the triangle's hypotenuse.
the original Pythagorean theorem is

where
a and
b are the two sides and
c is the hypotenuse.
that means the Pythagorean theorem for this question is:

or
Answer:
Two line are perpendicular when they are at right angles to each other.
The red line is perpendicular to the blue line in each of these examples:
Perpendicular Example
Step-by-step ex;planation: