This would work ...
SELECT MINCTE.Balance, MINCTE.Branch_City, MAXCTE.Balance, MAXCTE.Branch_City
FROM (select L.*, B.Branch_City from loan L
INNER JOIN branch B on L.Branch_Id=B.Branch_ID
order by Balance LIMIT 1) MINCTE
CROSS JOIN
(select L.*, B.Branch_City from loan L
INNER JOIN branch B on L.Branch_Id=B.Branch_ID
order by Balance desc LIMIT 1) MAXCTE
MINCTE is the derived table to get the minimum value and the associated city name
MAXCTE does the same for the maximum value
Those two derived tables are then CROSS joined