So you times the -2 with the bits inside the bracket so:
-2 x t= -2t
-2 x 4 2/3 = -9 1/3
So then that makes:
-2t - 9 1/3= 9 1/2
So to get what t equals you have to get it by itself so you add the -9 1/3 to both sides of the equation to get:
-2t=18 5/6
So then you divide by -2 on both sides to get
t=-9 5/12
Which is the answer. :-D