16-9= 19-9= 10-9=
9+=11 9+=17 9+=13
11-9= 17-9= 13-9=
-9 =
13-97 15-94 14-95
18-914-9 17-912-9 16-910-9
15-9+2= 16-9-3=
4+7-9= 18-9-7=
13-9=3+ 17-9=7+
14-4-5= 18-8-1=
=
=(只)