(y-4)(y+4)

The expression \((y-4)(y+4)\) can be simplified using the difference of squares formula, which states that: \[ (a-b)(a+b) = a^2 - b^2 \] In this case, we can let \(a = y\) and \(b = 4\). Therefore, we have: \[ (y-4)(y+4) = y^2 - 4^2 \] Calculating \(4^2\): \[ 4^2 = 16 \] Putting it all together: \[ (y-4)(y+4) = y^2 - 16 \] So, the simplified form of the expression is: \[ y^2 - 16 \]