Question 4821
Think about the minus sign as being a negative attached to the number immediately following it.  In the first example the negative is in front of the 3, so when you clear the parentheses, you will multiply -3 times what is inside (in this case it is seven)

If there is no number in front of the parentheses, it indicates the number one is in front, so you would multiply everything inside the parentheses by -1.

Example:

-3(4+3+x) = -3(7+x) = -21-3x
-3(4+3-x) = -3(7-x) = -21+3x
-(4+3+x) = -1(7+x) = -7-x