Side lengths with 6 in, 10 in, 18 will not form a triangle 'cause we know, that sum of shorter sides must be greater than the longer side but here it's not.
6 in, 10 in, 18 in The sides need to be in between (10-6) and (10+6) or between 4 and 16. But the third side here is 18, so that cannot qualify as a side.
