#### Answer

10

#### Work Step by Step

According to the last step of order of operations, we must evaluate addition and subtraction from left to right.
First, we only consider $-1-(-7)$. Change the minus sign to a plus sign and insert the opposite of the second number in place of the second number.
$-1-(-7)=-1+(7)=-1+7=6$
Next, we can add this to -4 by using the same process.
$6-(-4)=6+(4)=6+4=10$