normal curve

• Apr 12th 2008, 08:18 PM
andrewsx
normal curve
The normal to the curve represented by the equation y=x^2+6x+4 at the point (-2,-4) also intersects the curve at x=

A) -6
B) -9/2
C) -7/2
D) -3
E)-1/2
• Apr 12th 2008, 08:27 PM
Mathstud28
Ok
Quote:

Originally Posted by andrewsx
The normal to the curve represented by the equation y=x^2+6x+4 at the point (-2,-4) also intersects the curve at x=

A) -6
B) -9/2
C) -7/2
D) -3
E)-1/2

Just use the equation of the normal line $y-x_0=\frac{-1}{f'(x_0)}\bigg(x-x_0\bigg)$