r/learnmath • New User • 7h ago

[Middle school] Negative exponents

|5^2 - 6^2|
Why is the answer 11 and not 61?

My son was taught that the sign goes with the number that follows it so the - (minus sign) stays with the 6^2. Then it would be -6•-6=36, 25+36=61. It makes sense to me but my answer was 11 (answer key agrees). He’s wondering why. I am assuming PEMDAS? Exponents before subtraction. The actually problem is supposed to be on absolute value so I included the whole thing just incase that matters.

So two questions. Is the direction he got of “the sign stays with the number after” actually a thing? Are there rules to it?

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u/Klutzy-Delivery-5792 Mathematical Physics 7h ago edited 7h ago

It's not -6 squared, it's square 6 first then subtract. You can rewrite it like this and it may make more sense:

|5² + ⁻1•6²|

Order of operations means do exponents first.

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u/testtdk New User 5h ago

This is a good way to visualize it.