Let f( x, y ) = 7 - x2 + xy- 3y2. (a) Find f (2, 6) and f (2, 6). Fx (2, 6 ) = fy (2, 6) = (b) Interpret the numbers in part (a) as slopes. Of (2, 6) is the slope of the tangent line to the curve of intersection of the surface z = 7 - x + xy - 3y and the plane y = 6 at the point (2, 6, 0). f (2, 6) is the slope of the tangent line to the curve of intersection of the surface z = 7 - x2 + xy - 3y and the plane x = 2 at the point (2, 6, 0). Of (2, 6) is the slope of the tangent line to the curve of intersection of the surface z = 7 - x2 + xy - 3y and the plane y = 0 at the point (2, 6, -93). f (2, 6) is the slope of the tangent line to the curve of intersection of the surface z = 7 - x2 + xy - 3y and the plane x = 1 at the point (2, 6, -93). O f (2, 6) is the slope of the tangent line to the curve of intersection of the surface z = 7 - x2 + xy - 3y and the plane y = 6 at the point (2, 6, -93). f (2, 6) is the slope of the tangent line to the curve of intersection of the surface z = 7 - x2 + xy - 3yz and the plane x = 2 at the point (2, 6, -93). Of (2, 6) is the slope of the tangent line to the curve of intersection of the surface z = 7 - x2 + xy - 3y and the plane y = 2 at the point (2, 6, -93). f(2, 6) is the slope of the tangent line to the curve of intersection of the surface z = 7 - x2 + xy - 3y2 and the plane x = 1 at the point (2, 6, -93). (c) Interpret the numbers in part (a) as rates of change. Of (2, 6) is the rate of change of f(x, y) with respect to x with y held fixed with a value of 2. f (2, 6) is the rate of change of f(x, y) with respect to y with x held fixed with a value of 6. Of (2, 6) is the rate of change of f(x, y) with respect to x with y held fixed with a value of 6. f (2, 6) is the rate of change of f(x, y) with respect to y with x held fixed with a value of 0. O f (2, 6) is the rate of change of f(x, y) with respect to x with y held fixed with a value of 6. f (2, 6) is the rate of change of f(x, y) with respect to y with x held fixed with a value of 2. Of (2, 6) is the rate of change of f(x, y) with respect to x with y held fixed with a value of -34. f (2, 6) is the rate of change of f(x, y) with respect to y with x held fixed with a value of 2