Question 1007709
{{{9^(-x) = 1/3}}}



{{{9^(-x) = 3^(-1)}}} Rewrite the right side



{{{(3^2)^(-x) = 3^(-1)}}} Change 9 to {{{3^2}}}



{{{3^(-2x) = 3^(-1)}}} Use the <a href = "http://www.onlinemathlearning.com/image-files/387x248xari121.gif.pagespeed.ic.vFV2Lan_oa.png">third rule</a>



{{{-2x = -1}}} The bases are equal, so the exponents must be equal.



{{{-2x/(-2) = -1/(-2)}}}



{{{x = 1/2}}}