Question

crow and mai wrote expressions to answer the previous question.
crows expression: -2 + 3 - 5
mais expression: -2 + 3 - (-5)
who wrote a correct expression? circle one.
crow mai both neither
explain your thinking.

Explanation:

Step1: Simplify Crow's expression

$$\begin{align*} -2 + 3-5&=( -2+3)-5\\ &=1 - 5\\ &=-4 \end{align*}$$

Step2: Simplify Mai's expression

$$\begin{align*} -2 + 3-(-5)&=-2 + 3+5\\ &=( -2+3)+5\\ &=1+5\\ &=6 \end{align*}$$

Assuming the previous question was about a situation where the correct result is \(6\) (since \(a-(-b)=a + b\) in arithmetic of integers).

Answer:

Mai

Because when we simplify \( - 2+3-(-5)\), using the rule \(a-(-b)=a + b\), we get \( - 2+3 + 5=6\). While for \( - 2+3-5\), we get \(-4\). If the context (from the previous question) required the operation equivalent to \( - 2+3+5\) (i.e., subtracting a negative is adding a positive), then Mai's expression is correct.