Respuesta :

x^2+4x+4=8
-8                -8
subtract 8 from both sides 

x^2+4x-4=0

now factor using quadratic formula
ax^2+bx+c=0

x= -b +-[ (sqrt (b^2-4ac))/2a ]

x=-2(1+sqrt(2))


x= 2(sqrt(2) -1)

hope that helps, hopefully you know how to plug and chug into quadratic formula. if not you can ask for help