Question

3 which expression is equivalent to $-3(10m - 2) + (3 + 6m - 3)$?
a $-24m + 6$
b $-24m - 6$
c $-48m + 6$
d $-18m$
evelyn chose a as the correct answer. how might she have gotten that answer?

Explanation:

Step1: Expand the first term

$-3(10m - 2) = -30m + 6$

Step2: Simplify the second term

$(3 + 6m - 3) = 6m$

Step3: Combine the two results

$(-30m + 6) + 6m = -24m + 6$

Step4: Analyze Evelyn's error

Evelyn did not simplify the constant terms $3-3$ in the second parentheses, incorrectly treating $(3 + 6m - 3)$ as $3 + 6m$ instead of $6m$. Her calculation would be: $-30m + 6 + 3 + 6m - 3 = -24m + 6$.

Answer:

A. $-24m + 6$
Evelyn failed to simplify the $3 - 3$ in the second parentheses, incorrectly retaining the $+6$ constant term while combining the $m$-terms correctly: $-30m + 6m = -24m$, leading to $-24m + 6$.