Start by turning the mixed number to an improper fraction by multiplying the 3 and 4 to get 12 and then add on 3 to that to get 15/4.
So not you have -2/3 ÷ 15/4. Do the reciprocal of 15/4 to get 4/15 and change the ÷ to a x (that's multiplication sign. After that multiply. -2/3 x 4/15 and the answer would be -8/45 :)