First. Let's work with PEMDAS
P means we start with Parentheses
So distribute -3 making your equation
16-3x-18=-2x+17
Since we have like terms, we will combine them making it
-3x-2=-2x+17
Next. Let's move the -2x over to the other side, by adding
x-2=17
Then add two to both sides to get your answer.
x=19