Answer:
c and d
Step-by-step explanation:
Simplify a: 6x+7=4x+7 ~ No matter what, this cannot be possible
Simplify b: 6x=4x ~ Once again, this is impossible unless x=0, but I'll assume it can't be for now
Simplify c: 4x+7=4x+7 ~ This clearly is a correct statement, this it is c
Simplify d: 6x-1=4x+1 ~ By subtracting 4x on each side, then adding 1 on both sides, we get 2x=2, so x can be 2.
