[tex] \frac{x^{15}}{x^{?}} = x^{10} [/tex]
When two exponents that have the same base are divided, it's the same as subtracting their exponents. For example, you can rewrite the equation like this:
[tex] x^{15-?} = x^{10} [/tex]
Then, you can rewrite the x^10 as x^(15-5):
[tex] x^{15-?} = x^{15-5} [/tex]
Therefore, the ? must be equal to 5 (b).
[tex] ? = 5 [/tex]
