Let \(\mathbf{a}\) and \(\mathbf{b}\) be vectors such that \(\|\mathbf{a}\| = 5,\)\(\|\mathbf{a} + \mathbf{b}\| = 7,\)and\(\|\mathbf{a} - \mathbf{b}\| = 9.\) Find \(\|\mathbf{b}\|.\)
The magnitude of vector v is 5*sqrt(3).
