Question #9eb44

1 Answer
Ryan
Oct 30, 2017

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?

Related questions
Impact of this question
773 views around the world
You can reuse this answer
Creative Commons License