# Math Help - Conic Sections and polar coordinates

1. ## Conic Sections and polar coordinates

Hello

I'm stuck on this question Word for word from the text
"A.) decide whether the equation
$$9x^2+6xy+y^2-12x-4y+4=0$
$

represents a parabola an elipse or a hyberbola
b.) show that the graph of the equation in part A is the line $y=-3x+2$

my problem is that I cannot find the angle, in all the othe questions the angle worked out to be a special triangle but in this one I have tried applying $tan 2\alpha =\frac{B}{A-c}$ but I get an angle of 1/3
any help would be appreciated

2. B= 6, A= 9 and C= 1? so $tan(2\alpha)= \frac{6}{9- 1}= \frac{3}{4}$. arctan(3/4) is about .6435 radians so that $\alpha$ is, indeed, approximately 1/3 radian. What's wrong with that?