We have the expression:

In order for other expression being the same, the total value of the exponent should be 9 and the base 7. That's why the following are the equivalent expressions:



These, when operated give as result the original expression 7^9.
*The first one, since we will have the same base and sustrac the exponent of the number dividing from the exponent of the number divided.
*The second one, since we have the same base and multiply the exponents.
*The third one, since we have the same base and add the exponents.