1. Move the decimal point to the left until you have a number between 1 and 10. In this case, you'll move it four places to the left: 7.3000

2. Count the number of places you moved the decimal. Since you moved it four places to the left, the exponent will be 4.

3. Write the number in the form of a x 10^b, where 'a' is the number between 1 and 10 and 'b' is the exponent.

Therefore, 73,000 in scientific notation is 7.3 x 10^4.