x = 6.
Explanation:
Well we know that x + 12 must equal 3x, because the length of a cone is the same no matter where you look at it. Now we must write it out as an algebraic equation to solve for x
x+ 12 = 3x
1) We want to have x just on one side, so we subtract 1x (or x) from both sides
x - x + 12 = 3x - x
12 = 2x
2) We wan to have one x instead of 2, so we divide both sides by 2
12/2 = 2x/2
6 = x
x = 6