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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