The senior classes at High School A and High School B planned separate trips to New York City. The senior dass at High School A rented and filled 14 vans and 6 buses with 264 students. High
School B rented and filled 7 vans and 5 buses with 178 students. Every van had the same
number of students in it as did the buses. How many students rode in each van?

the graph on the bottom right

0.02040816326

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.