Answer:
8
Explanation:
The minus sign outside parentheses changes the sign of what's inside parentheses when parentheses are eliminated:
7 -(-1) = 7 +1 = 8
_____
Alternate way to think about it
Subtraction is the same as addition of the opposite. The opposite of -1 is +1, so subtracting -1 is the same as adding +1.