Simplify expressions with exponents and just two variables.[br]For video explanation of the topic, go to[br][url]https://www.khanacademy.org/math/arithmetic/exponents-radicals/negative-exponents-tutorial/v/negative-exponents[/url].[br]Videos with negative exponents at[br][url]http://patrickjmt.com/exponents-simplifying-expressions-with-negative-exponents-ex-1/ [/url][br]or [url]http://patrickjmt.com/exponents-simplifying-expressions-with-negative-exponents-ex-2/[/url][br]or [url]http://patrickjmt.com/exponents-simplifying-expressions-with-negative-exponents-ex-3/[/url]