# What are the extrema and saddle points of #f(x, y) = x^2 + y^2+27xy+9x+3y#?

##### 1 Answer

Aug 26, 2016

#### Answer:

A saddle point is located at

#### Explanation:

The stationary poins are determined solving for

obtaining the result

The qualification of this stationary point is done after observing the roots from the charasteristic polynomial associated to its Hessian matrix.

The Hessian matrix is obtained doing

with charasteristic polynomial

Solving for