Uaoy dx point p(13,6) is 5. if the equation of the tangent plane to the surface z = 16 - x -y at the point pr1 ax+ by + cz + d = 0, then the value of |d| is (b)

UAOY dX point P(13,6) is 5. If the equation of the tangent plane to the surface z = 16 - x -y at the point Pr1 ax+ by + cz + d = 0, then the value of |d| is (b) 26 (C) 36 (d) 46 (a) 16 6. If the directional derivative of the function z=ve2 at (2-1 alono ihe init wa