The answer is 12.
since we also know that jack is 2 times lucy now then the entire formula would be 2x - 6 = 18 to solve we add 6 to both sides 2x - 6 + 6 = 18 + 6 the 6s on the left cancel because when you have a positive and negative of the same number it always = 0 we get 2x = 24 then divide both sides by 2 to get the answer 2x / 2 = 24 / 2 the 2s on the left cancel and you get