(b+3) (b-3)

The expression \((b+3)(b-3)\) is a difference of squares. You can expand this expression using the formula \( a^2 - b^2 = (a+b)(a-b) \). Here, \(a = b\) and \(b = 3\). Therefore: \[ (b+3)(b-3) = b^2 - 3^2 \] This simplifies to: \[ b^2 - 9 \] So, \((b+3)(b-3) = b^2 - 9\).