Answer :
Expanded form means making a number into an equation that makes your number the sum. It is a way to represent the value of each digit in a number.
One possible answer could be:
12,000,000 + 400,000 + 30,000 + 90
= 12,430,090
One possible answer could be:
12,000,000 + 400,000 + 30,000 + 90
= 12,430,090