Chapter 8.1, Problem 4E

For each function in Exercises 1–4, evaluate

(a) $f\left(0,0\right)$;

(b) $f\left(1,0\right)$;

(c) $f\left(0,-1\right)$;

(d) $f\left(a,2\right)$;

(e) $f\left(y,x\right)$; and

(f) $f\left(x+h,y+k\right)$;

[Hint: See Quick Examples 1–3.]

$f\left(x,y\right)=0.4x-0.5y-0.05xy$