9+7= 11-2= 8+6= 16-8=
8+9= 13-7= 6+7= 11-6=
14-6= 14-8= 17-9= 15-5=
12-5= 12-9= 16-7= 11-7=
14-5+8= 16-9+8= 17-7+9=
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