Is that what you are looking for?
I only simplified the brackets and replace an 'x' by 'times', and simplified the denominator a little and added dx.
As you can see, the denominator and numerator can be further simplified.
Can you continue now?
EDIT: Since the 'x' is an actual x, this becomes:
Actually, the limits flip, but the overall sign does NOT change. That's because you get one minus sign for the differential, and one minus sign for the lone x in the numerator. So you get
Now, what happens when you flip the right integral's limits back to what they are on the LHS?