Answer:
1000+80+4+0.9
Step-by-step explanation:
Keep in mind that expanded form means to expand the number by adding the individual places values to form a mathematical expression. In other words, numbers are expanded to show the value of each of its digits.
For the thousands place:
1,084.9 ---> 1,000.0
Hundreds place:
Because the value is 0, you needn't to include it in the expression.
Tens place:
1,084.9 ---> 80.0
Ones place:
1,084.9 ---> 4
Tenths place:
1,084.9 ---> 0.9