Question

solve this by completing the square..
x2 + 4x – 12 = 0

Answer 1

I don't know why no one helps you

Answer 2

wolframalpha does http://www.wolframalpha.com/input/?i=x%5E2+%2B+4x+%E2%80%93+12+%3D+0+

Answer 3

take half of 4, then square. (4/2)^2 = 4. That's the number that needs to be on the end
x^2 + 4x +4 -4-12= 0
Then factor
(x+2)^2 - 16 = 0
(x+2)^2 = 16
x+2 = +-4
x=-2+-(-4) = 2,-6

Answer 4

(x^2+4x) - 12 = 0

x^2 + 4x + (4/2)^2 -(4/2)^2 - 12 = 0

x^2 + 4x + 2^2 - (2)^2 - 12 = 0

(x+2)^2 - 4 - 12 = 0

(x+2)^2 - 16 = 0