9
does it look like ? if so, it is the base.
remember what a logarithm is, logarithms are powers.
Definition: the logarithm of a number to a given base is the power to which the base must be raised to give the number.
that is, if then
example, since we have to raise the base 2 to the power 3 to get 8
now, is the power we have to raise to to get 9. so what number is that?