Question 724392
let side of cube be s

6 times volume of cube= 6s^3

surface area = 6s^2
length of 12 edges = 12s

6s^3= 6s^2+12s

divide by 6s

s^2=s+2

s^2-s-2=0

s^2+2s-s-2=0

s(s+2)-1(s+2)=0

(s+2)(s-1)=0
s=-2 or 1

ignore negative

side = 1 unit