The first step for solving this expression is to remove the first set of parenthesis.
-8.3x + 4 - (3.2x - 5)
Remember that when there is a "-" sign in front of the parenthesis,, we must change the sign of each term in the parenthesis. This will change the expression to the following:
-8.3x + 4 - 3.2x + 5
Collect the like terms with an x variable.
-11.5x + 4 + 5
Lastly,, add the numbers to get your final answer.
-11.5x + 9
Let me know if you have any further questions.
:)