Given that $f$ is a differentiable function with $f(1,1)=1\mathrm{.}9,f_x(1,1)=3,$ and $f_y(1,1)=4,$ use a linear approximation to estimate $f(1\mathrm{.}1,0\mathrm{.}9)$

Select one:

$1\mathrm{.}9$

$2\mathrm{.}2$

$2\mathrm{.}1$

$2$

$1\mathrm{.}8$