Fred tried to evaluate an expression step by step. \[ \begin{aligned} & (-10+6)-5 \\ = & -4-5 \\ =-4+(-5) & \text { Step 1 } \\ = & \text { Step 2 } \\ = & \text { Step 3 } \end{aligned} \] Find Fred's first mistake. Choose 1 answer: (A) -10 plus 6 equals -16 not -4 .

Oops! Fred's mistake isn't with the addition of -10 and 6; he correctly calculated that -10 + 6 equals -4. It looks like Fred's first error actually occurred later when subtracting 5 from -4. Instead of correctly calculating -4 - 5, which equals -9, he might have been confused about how to approach the operation. To clarify things a bit, Fred primarily needs to remember that subtracting a positive number is the same as adding a negative. So, -4 - 5 can also be seen as -4 + (-5)!