Solve the following quadratic equation by factoring?

Question

x^2 + 11x = -18

the solution set is{ _____ }

Answer 1

x^2 + 11x = -18

bring the -18 over to the left side of the equation

x^2 +11x +18 = 0

find factors of 18 that add up to 11

they are 9 and 2 (9+2=11)

replace the 11x with 9 and 2

x^2 + 9x + 2x +18 = 0

then factor in pairs by splitting the equation in half and then factoring both halves

x^2 +9x and 2x +18

x(x+9) and 2(x+9)

so you have (x+2)(x+9) as your answer

try this website for easy answers: www.quickmath.com

Answer 2

(x+3)(x+8)

only cuz im bored

Answer 3

x^2 + 11x = -18

=> x^2 + 11x + 18 = 0

=> x^2 + 9x + 2x + 18 = 0

=> (x^2 + 9x) + (2x + 18) = 0

=> x (x + 9) + 2 (x + 9) = 0

=> (x + 2) (x + 9) = 0

=> (x + 2) = 0 OR (x + 9) = 0

=> x = -2, -9

Therefore, the solution set is{ -2, -9 }