Update solution.md

Author: usernamehw

1-js/05-data-types/05-array-methods/4-sort-back/solution.md

@@ -3,7 +3,7 @@
 ```js run
 let arr = [5, 2, 1, -10, 8];
 
-arr.sort((a,b) => b - a);
+arr.sort((a, b) => b - a);
 
 alert( arr );
 ```