You can
put this solution on YOUR website!For the equation

You may have made a careless mistake in your answer.
If you expand the equation you gave, the first term would be

because you have

.
The correct answer is:
For the second equation

Your answer has a tiny common error.
You also made the same error as above.
The first part is correct.

You should know that whenever you square a negative number, it beccomes positive.
The correct answer is:
Hope this helps!