If #5^x = 3#, what does #5^-(2x)# equal?
1. First, take the log (base 10) of both sides.
2. When you have an exponent inside of a log, you can take that exponent out and multiply it by the rest of the log.
This is known as the power rule of logarithms.
3. Now divide both sides by
4. Now, plug
Let's evaluate the power first. (I used a calculator here.)
Hope this helps! :)