Question

Determine if the graph is symmetric about the x-axis, the y-axis, or the origin.

r = -3 - 2 cos θ

The answer I chose is y-axis only. But the other answers are no symmetry, origin only and x-axis only.

Answer 1

Am I right?

Answer 2

i think so

Answer 3

@Helpme323 @iGreen @mathmath333 help?

Answer 4

Or is it x-axis? I think it might be that one after looking back at the graph.

Answer 5

@aum @CuteGirl903k @IM5er101 @just_one_last_goodbye @No.name @puppylover123 @TheSmartOne I just need someone to check this. I think it might be the x-axis. Am I right?

Answer 6

sorry idk this!! : /

Answer 7

\[\begin{array}{c|l}
r(\theta)=\cdots&\text{Symmetry}\\
\hline
r(-\theta)&\text{x axis}\\
\hline
r(\pi-\theta)&\text{y axis}\\
\hline
-r(\theta)&\text{origin}
\end{array}\]
Given \(r=-3-2\cos\theta\), you would check to see if this expression is equivalent to any of the other forms.
\[r(\theta)=-3-2\cos\theta\\
r(-\theta)=-3-2\cos(-\theta)=\cdots\]
If these are the same, you have symmetry about the x axis.

Answer 8

It's okay @puppylover123 thanks anyway

Answer 9

Im good at english tho!! lol

Answer 10

if u have a question in english post it and tag me :)

Answer 11

Thank you @SithsAndGiggles !! :)

Answer 12

yw

Answer 13

@puppylover123 Thanks I'll keep that in mind!