Find both first partial derivatives of f(x, y) = 7x - 2y + 8?
1) f_x(x, y) = 7
2) f_x(x, y) = -2
3) f_x(x, y) = 0
4) f_x(x, y) = 8
5) f_y(x, y) = 7
6) f_y(x, y) = -2
7) f_y(x, y) = 0
8) f_y(x, y) = 8