# Operations mistake

Algebra Level 2

Vikram has been working with Order of Operations all day, and has a strong sense that

$(-a) + b = b - a,$

but doesn't know why. How many of the $$11 \times 11$$ ordered pairs of integers $$(a, b)$$, where $$a$$ and $$b$$ are integers from 0 to 10 (inclusive) , are there, such that

$(-a) + b = b-a?$

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