6. A used-book store sells paperback books for $1.30, with a $0.25 discount for each book more than 5 that a customer buys. A customer bought some books last week for $13.85. The store has a sale this week. The
price for each book is $1.15, with the same discount on each book over 5 purchased. How much would the
customer save if the same books were bought this week?
$12.05
b. $1.80
$0.05
d. $1.63
a.
c.

109 trust me

step-by-step explanation:

okay wait before i answer, is this for your points on a graph?

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.