Solve x2 + 12x = –11 by completing the square. Which is the solution set of the equation?

Step-by-step explanation:

x2 + 12x = –11

x2 + 12x +36 = –11 + 36

(x+6)^2 = -11 + 36 = 25 = (+/- 5)^2

x+6 = +/- 5

x+6 = +5  => x=-1

x+6 = -5  => x = -11

So the solution set is S = {-1, -11}

i pretty sure it is

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.