$(5$ points$)$

Find the linearization of the function f$($x$,$y$)=1894$x$24$y$2$

at the point $(-4,5).$

L$($x$,$y$)=$

$(32/5)$x$-8$y$-9\mathrm{.}4$

Use the linear approximation to estimate the value of f$(4\mathrm{.}1,5\mathrm{.}1)$

$=$