The upper left-hand corner of a piece of paper 8 in. wide by 17 in. long is folded over to the righthand edge as in the figure. How would you fold it...

The upper left-hand corner of a piece of paper 8 in. wide by 17 in. long is folded over to the righthandedge as in the figure. How would you fold it so as to minimize the length of the fold? In otherwords, how would you choose x to minimize y?