Question

14-6=14-4
15-9=15-5
11-8=11-1
12-8=10-8
13-7=10-7
16-8=10-8

Answer 1

14-6=(14-4)-2=10-2=8
15-9=(15-5)-4=10-4=6
11-8=(11-1)-7=10-7=3
12-8=2+(10-8)=2+2=4
13-7=3+(10-7)=3+3=6
16-8=6+(10-8)=6+2=8