something noteworthy, the y-coordinate for each point is the same, 9⅛, that means is a horizontal line, over which the x-coordinates are at, so since it's a horizontal line, all we need to do is find, what's the distance between

of course, let's firstly convert the mixed fraction to improper fraction and then check their difference.
![\bf \stackrel{mixed}{5(7)/(10)}\implies \cfrac{5\cdot 10+7}{10}\implies \stackrel{improper}{\cfrac{57}{10}} \\\\[-0.35em] ~\dotfill\\\\ \cfrac{2}{5}-\left[-\cfrac{57}{10} \right]\implies \cfrac{2}{5}+\cfrac{57}{10}\implies \stackrel{\textit{using the LCD of 10}}{\cfrac{(2)2+(1)57}{10}}\implies \cfrac{4+57}{10}\implies \cfrac{61}{10}\implies 6(1)/(10)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ieijb6f4t68z8yhweywefvph05erfhzeko.png)