If `|veca+vecb|=|veca-vecb|`, then what is the angle between `veca " and "vecb`?

Explanation

To solve the problem, we start with the given condition:

\[ |\vec{a} + \vec{b}| = |\vec{a} - \vec{b}| \]

### Step 1: Square both sides
We square both sides of the equation to eliminate the absolute values:
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