Let $f(x, y)=x^{2}-4 x y-y^{2}$. Compute $f(4,0)$ and $f(4,-6)$ $f(4,0)=\square$ (Simplify your answer.) $f(4,-6)=\square$ (Simplify your answer.)

Step 1 ：Substitute x = 4 and y = 0 into the function: \(f(4,0) = (4)^{2} - 4*(4)*(0) - (0)^{2}\)

Step 2 ：Simplify the expression: \(f(4,0) = 16 - 0 - 0 = 16\)

Step 3 ：\(\boxed{f(4,0) = 16}\)

Step 4 ：Substitute x = 4 and y = -6 into the function: \(f(4,-6) = (4)^{2} - 4*(4)*(-6) - (-6)^{2}\)

Step 5 ：Simplify the expression: \(f(4,-6) = 16 - (-96) - 36 = 16 + 96 - 36 = 76\)

Step 6 ：\(\boxed{f(4,-6) = 76}\)