General Form: Circles

[ksmith81]

I have no idea how to write the general form for the circle centered at (6,3) with a radius of 9. Please help me!!!!

I do know that the formula is x^2+y^2+ax+by+c=0. I am completely lost.

 

[hongsgirl]

Hi ksmith8

The general equation of circle is :

\(\displaystyle (x-a)^2 + (y-b)^2=r^2\)

where : (a,b) is the center and r is radius

 

[mmm4444bot]

… The general equation of circle is :

\(\displaystyle (x-a)^2 + (y-b)^2=r^2\)

where : (a,b) is the center and r is radius

No, Girl. You've posted the standard equation of a circle.

The general equation appears in ksmith81's post.

To get those values of a, b, and c, in the general form as posted, we start by substituting the given information into the standard form, followed by expanding, collecting like-terms, and moving everything to one side.

You can see examples of this procedure HERE.

 

[hongsgirl]

Re:

[/quote]

No, Girl. You've posted the standard equation of a circle.

The general equation appears in ksmith81's post.

To get those values of a, b, and c, in the general form as posted, we start by substituting the given information into the standard form, followed by expanding, collecting like-terms, and moving everything to one side.

You can see examples of this procedure HERE.

[/quote]

Ah i see. Thanks for correcting my mistake, mmm4444bot