X - y = 11 and 2x + y = 19 by elimination

(14,3)

Step-by-step explanation:

2x + y = 19

x - y = 11

-2(x - y) = -2(11)

-2x + 2y = -22

-2x + 2y = -22 + 2x + y = 19

3y = -3

y = 3

x - y = 11

x - 3 = 11

x = 11 + 3

x = 14

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.