Example 1 — Three jobs of '$-$'
EasyProblem
In , , and , what does each '' do?
Solution
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Each '' could be a sign, an operation, or 'opposite of.'
Name the structure before touching arithmetic — that is what makes the right method obvious.
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Ask the recognition question: Does this symbol have more than one possible meaning that only context resolves?
If the answer is yes, the concept applies; the cue, not a keyword, decides the method.
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Read each by its context.
The rule is chosen only after the structure matches, so the steps mean something.
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is a negative number; is subtraction; is 'opposite of .'
Keep units, shape, or answer form tied to the story so the work does not become symbol pushing.
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Check the answer against the original question.
It should fit the mental model — one symbol, many jobs. If it does not, revisit the recognition step before changing the arithmetic.
Answer
Sign, operation, 'opposite of'
Takeaway: The same symbol's meaning is set by where it sits.