Question

Question #9eb44

Answer 1

I also got `16/3` (`=-5.333`) using two different methods.

Explanation:

Hmm, I tried it using implicit differentiation, using the exact same process as you, and got the same answer.

I also got it in `y = ...` form to find `dy/dx` using the standard differentiation rule:

`5x^2 + 4x +xy = 3`
`:. x(5x + 4 + y) = 3`
`:. y = 3/x -5x -4`
`= 3x^-1 - 5x -4`
`:. dy/dx = -3x^-2 -5`

`dy/dx= -3/x^2 - 5`

When you substitute `x=3` into that you should get exactly the same thing.

Does this help?