Please help with the questions below. Thanks!!

Problem 9. (1 point) Find the indicated partial derivatives of: 1x - 2y f ( x, y ) = 1x + 2y at the point (x, y) = (1,2). of (1, 2 ) = - 24 (1,2) = Problem 10. (1 point) Find the indicated partial derivatives of: z =In( x*+y) 98 918 Problem 11. (1 point) Find the indicated partial derivatives of: 5x Z = Vx2 + 12 98 918 Problem 12. (1 point) Find the indicated partial derivative: y + 3x Generated by @WeBWork, http://webwork.maa.org, Mathematical Association of America