You won't be able to solve that in terms of "elementary functions". You could, however, rewrite it as so that and then, letting y= -x, .

Now, use "Lambert's W function" which isdefinedas "the inverse function to ". Taking W of both sides, W(ye^y)= y= W(-2). Since y= -x, -x= W(-2) and x= -W(-2).