Evaluate the expression. [(3 to the power of –5)(3 to the power of 4)] exponent of 3

I'm assuming this is what that looks like .  We need to work inside those brackets first since the base is the same on both those expressions.  The base is a 3.  When we multiply like bases the rule is that we add the exponents, so what we have after that is .  Now the rule is power to power.  Multiply them.  is your answer if you leave the exponent as a negative, if you need it positive.