(1)∵f+v-e=2
∴x=f+v-2=6+8-2=12,y=2+e-f=2+12-8=6
(2)m+n即面数f.∴m+n=f=2+e-v=2+18*4/2-18=20
(3)∵m+n=20 m+2q=18
∴n=2+2q
∴(3n-6q)²-2/(10q-5n)=(6+6q-6q)/(10q-10-10q)=6/(-10)=-3/5
(1)∵f+v-e=2
∴x=f+v-2=6+8-2=12,y=2+e-f=2+12-8=6
(2)m+n即面数f.∴m+n=f=2+e-v=2+18*4/2-18=20
(3)∵m+n=20 m+2q=18
∴n=2+2q
∴(3n-6q)²-2/(10q-5n)=(6+6q-6q)/(10q-10-10q)=6/(-10)=-3/5