Hmm. It looks like we might not have the whole problem here. Is there a value for AB? or is X the midpoint of segment AB?If X is the midpoint you can set the two statements equal to each other and then solve for x:2x + 11 = 4x - 5I'd subtract 2x from both sides, giving:11 = 2x - 5Then add five to both sides:16 = 2xThen divide both sides by 2:x = 8