Been trying so hard

Solve for http://webwork.mathstat.concordia.ca...dd0b8b8e91.png :http://webwork.mathstat.concordia.ca...e051ab8341.png

so I come up with

log_{3}x+log_{3}(x+3) I combine them into log_{3}(x^2+3x)-log_{3}6=0

then I tired to make it into a quadratic formula to solve it that way but didn't work.

Do I need to change it into exponent form to solve?