Let's analyze Brandon's steps to see if he properly solved the equation \( 15x + 6 = 14x + 5 \).
Step 1: Add 14 negative x-tiles to both sides.
- This means he is subtracting \( 14x \) from both sides, resulting in: \[ (15x - 14x) + 6 = (14x - 14x) + 5 \] Simplifying both sides gives: \[ 1x + 6 = 0 + 5 \] or: \[ x + 6 = 5 \]
Step 2: Add 5 negative unit tiles to both sides.
- This means he is subtracting \( 5 \) from both sides, resulting in: \[ x + (6 - 5) = 0 \] Simplifying gives: \[ x + 1 = 0 \] or: \[ x = -1 \]
So in actuality, after performing both steps properly, Brandon should have found \( x = 1 \) in step 3. However, after reviewing his steps, the correct conclusion should have been \( x = -1 \) based on proper arithmetic.
Now evaluating the statements:
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"Brandon is correct because he has the correct solution in step 3." - In fact, he doesn’t have the correct solution.
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"Brandon is correct because he forms zero pairs to isolate the variable by using the lowest coefficient each time." - This statement is vague and doesn't confirm whether he has obtained the correct solution, plus he actually didn't form zero pairs properly to arrive at the answer.
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"Brandon is not correct because he should have performed step 2 before performing step 1." - The order of the steps is not inherently incorrect, so this statement doesn't indicate why he is wrong.
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"Brandon is not correct because he should have added 6 negative unit tiles to isolate the variable in step 2." - This statement identifies that his isolation process in step 2 was flawed; he should have subtracted 6 instead to isolate x.
Ultimately, the best explanation for why Brandon is incorrect is option 4.
Thus, the most accurate choice would be: "Brandon is not correct because he should have added 6 negative unit tiles to isolate the variable in step 2."
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