Question

How do you fill in the blank for the expression `9^3*9^?=9^7`?

Answer 1

The answer is 4.

Explanation:

`a^n xx a^n = a^(n-m)`

`9^3 xx 9^? = 9^7`
`9^(3+?) = 9^7`
`3 + ? = 7`
`? = 4`