A friend of yours wants to teach a dance class after school. She needs to rent a dance studio to teach the class, and the cost of rent is $400 for 12 weeks. The class will meet each week and your friend will charge each student the same fee for the whole course. Your friend's profit depends on how many students enroll in the course and how much she charges each student. If your friend charges each student D dollars for the course, define a function, p, that relates the number of students who take the dance course, n, to the profit, p(n).

Step-by-step explanation:

As per given we have:

Profit is going to be:

solution:

the given function is ,

      =

the three roots of this quadratic function is , 0 ,8 and 10.all the roots are real and rational.

if a quadratic equation is of the form ,

sum of the roots = a + b +c= 0+8+10=18=  

product of roots taken two at a time = a b + b c+ c a = 0+80+0=80 =  

product of roots = a b c = 0=  

there are 11 doors in a hall starting from 0 to 11.the entry in the hall is permitted through gate number 0 and exit is allowed through only gate number 8 and 10.so, three roots(0,8,10) of quadratic function is given by entry and exit route of this hall.

126 maybe. sorry