Answer
$$f\left( { - 1,2} \right) = 23{\text{ and }}f\left( {6, - 3} \right) = 594$$
Work Step by Step
$$\eqalign{
& f\left( {x,y} \right) = 2{x^2}{y^2} - 7x + 4y \cr
& {\text{find }}f\left( { - 1,2} \right).{\text{ substitute }} - 1{\text{ for }}x{\text{ and }}2{\text{ for }}y \cr
& f\left( { - 1,2} \right) = 2{\left( { - 1} \right)^2}{\left( 2 \right)^2} - 7\left( { - 1} \right) + 4\left( 2 \right) \cr
& {\text{simplifying}} \cr
& f\left( { - 1,2} \right) = 8 + 7 + 8 \cr
& f\left( { - 1,2} \right) = 23 \cr
& \cr
& {\text{find }}f\left( {6, - 3} \right).{\text{ substitute 6 for }}x{\text{ and }} - 3{\text{ for }}y \cr
& f\left( {6, - 3} \right) = 2{\left( 6 \right)^2}{\left( { - 3} \right)^2} - 7\left( 6 \right) + 4\left( { - 3} \right) \cr
& {\text{simplifying}} \cr
& f\left( {6, - 3} \right) = 648 - 42 - 12 \cr
& f\left( {6, - 3} \right) = 594 \cr} $$
