The answer is: x = 9
Here's how I got my answer:
Step 1: Simplify the brackets. Which leaves us with

Step 2: Expand it. Which leaves us with

Step 3: Simplify
to
. Which leaves us with

Step 4: Subtract 13 from both sides. Which leaves us with

Step 5: Simplify
to 27. Which leaves us with

Step 6: Divide both sides by 3, leaving us with our answer, x = 9.