so solve for ?
we use commutative which is a(bc)=(ab)c or also =abc
remember that (? times 7)=1(? times7)=1 times ? times 7=? times 7=7?
and
-(? times 3)=-1(? times 3)=-1 times ? times 3= -? times 3=-?3=-3?
so we have
8 times 4=7?-3?
7? means 7 times ? so therefor 7?-3?=7 times of ? -3 times of ?=7-3=4 times of ? so 4?
8 times 4=4?
multiply divide both sides by 4
8=?