If 8,6,2=4; 12,5,8=15; 13,10,x=18 then what would be x?

8-6+2=4; 12-5+8=15; 13-10+15=18. so X=15.

15

a,b,c=d a+c-b=d

13+15=28-10=18

8-6+2=4 12-5+8=15 13-10+15=18 SO X=15

IF 1,3,3=5 9,7,4=8 11,14,10=15 20,16,12=18 Than 3,6,7=?

If 2,6=5 4,9=7 6,11=8 8,15=11 then 12,18=?