So the question ask to find the displacement vector and the distance from the submarine to the boat. Base on my calculation the displacement value of the given data you give is <(5-3),(1-4)(-5-0)>. I hope you are satisfied with my answer and feel free to ask for more
7x would be 7 times whatever x is. then you subtract 11 from 7x. the reason you’re subracting 11 from 7x is because 11 has to be less than 7x (i understand negatives, but we’re not using that in this problem.)