Answer:
what is to be done in this case is to use the Micro-ATX motherboard in the ATX case.
Step-by-step explanation:
ATX and Micro ATX are different because ATX is a rectangle board with dimensions of 305mm by 244mm, whilst Micro ATX is a square board with dimensions of 61mm by 244mm.
From the above, it can be observed that the ATX case is bigger than the Micro ATX motherboard.
Therefore, what is to be done in this case is to use the Micro-ATX motherboard in the ATX case.