Whoever gets 25 points i really need ! : )

What is the approximate total length of iron edging needed to create the square frame and the two diagonals?

Sara needs to take a taxi to get to the movies the taxi charges $4.00 for the first mile and then $2.75 for each mile after that if the total charge is $20.50 then how far was sara’s taxi ride to the movie

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?