Cara used the order of operations to evaluate the expression below.

[tex]\[
\begin{array}{c}
\frac{4(7-13)}{3} + (-4)^2 - 2(6-2) \\
\frac{4(-6)}{3} + (-4)^2 - 2(4) \\
\frac{-24}{3} + 16 - 8 \\
-8 + 16 - 8 \\
0
\end{array}
\][/tex]

What was Cara's first error?

A. Cara did not evaluate [tex]\(7-13\)[/tex] correctly.
B. Cara did not evaluate [tex]\((-4)^2\)[/tex] correctly.
C. Cara subtracted 2 from 6 incorrectly.
D. Cara multiplied 2 and 4 incorrectly.



Answer :

Let's carefully examine the steps Cara took to evaluate the expression [tex]\(\frac{4(7-13)}{3} + (-4)^2 - 2(6-2)\)[/tex].

### Cara's Steps:
1. Step 1:
[tex]\[ \frac{4(7-13)}{3} + (-4)^2 - 2(4) \][/tex]
Cara simplified [tex]\(6-2\)[/tex] correctly to 4, but let's look closely at the step with [tex]\(7 - 13\)[/tex].

2. Step 2:
[tex]\[ \frac{28-13}{3} + (-4)^2 - 2(4) \][/tex]
Here, Cara seems to have evaluated [tex]\(4(7-13)\)[/tex] incorrectly. She wrote [tex]\(28 - 13\)[/tex] instead of correctly evaluating the subtraction [tex]\(7 - 13\)[/tex], which leads to [tex]\(-6\)[/tex].

### Correct Steps:
Let's consider how the expression should have been evaluated correctly:

1. Step 1:
[tex]\[ 7 - 13 = -6 \][/tex]
Therefore,
[tex]\[ 4(7-13) = 4(-6) = -24 \][/tex]
The expression should be:
[tex]\[ \frac{-24}{3} + (-4)^2 - 2(6-2) \][/tex]

2. Step 2:
[tex]\[ \frac{-24}{3} + 16 - 2(4) \][/tex]
Dividing [tex]\(-24\)[/tex] by 3:
[tex]\[ \frac{-24}{3} = -8 \][/tex]

3. Step 3:
Calculation for:
[tex]\[ (-4)^2 = 16 \][/tex]

4. Step 4:
Calculation for:
[tex]\[ 6 - 2 = 4 \quad \text{and} \quad 2(4) = 8 \][/tex]

5. Compiling Everything:
[tex]\[ -8 + 16 - 8 = 0 \][/tex]

From this walkthrough, the first error Cara made was in evaluating the subtraction [tex]\(7 - 13\)[/tex]. Instead of simplifying [tex]\(7 - 13\)[/tex] to [tex]\(-6\)[/tex], she erroneously seemed to have evaluated [tex]\(4(7-13)\)[/tex] as [tex]\(4(7) - 13 = 28 - 13\)[/tex].

### Conclusion:
Cara's first mistake was not evaluating [tex]\(7 - 13\)[/tex] correctly. Therefore, the correct answer is:

Cara did not evaluate [tex]\(7-13\)[/tex].

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