Solve x2 12x = –11 by completing the square. Which is the solution set of the equation? {–11, –1} {–11, 1} {11, –1} {11, 1}

is  -11,-1}

Explanation:

because  ince quadratic coefient is 1 (term in front of x^2)

take 1/2 of linear cofient (12) and square it

12/2=6, 6^2=36

add that to both sides

x^2+12x+36=-11+36

factor perfect square

(x+6)^2=25

sqrt both sides and take positiv and negative roots

x+6=+/-5

minus 6 both sides

x=-6+/-5

x=-6+5 or x=-6-5

x=-1 or -11