Consider the scalar$-$valued function:

$f(x,y)=xy-e^{5x+4y}$

$If$ you graph this function $asz=xy-e^{5x+4y}$ you will get a surface $in$ three dimensional space.

Find the equation $of$ the tangent plane $to$ this surface $at$ the point $(1,0,-e^5).$ Make sure $to$ submit a clear,

complete, and detailed solution.