Houston elementary school is selecting students to be in the winter festival show. there are 4 roles left but there are 12 students interested in the roles. how many combinations of the twelve students can be chosen for the four remaining roles? a. 505 b. 495 c. 48 d. 16

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.

i'm sorry i don't know

step-by-step explanation: