Write the standard form of the equation of the circle with the given characteristics.
Center: (4, −4); solution point: (1, 0)

Question

anonymous · Answer

what is the radius of the circle?

anonymous · Answer

Well, i guess (1,0) is on the circle so i guess r=sqrt((1-4)^2+(0+4)^2)

anonymous · Answer

I guess

anonymous · Answer

(x-4)^2+(y+4)^2=r^2, other people feel free to chime in as to what r is.

anonymous · Answer

(x-4)^2+(y+4)^2=a^2,where a is the radius

jamesj · Answer

The general form of the equation of a circle centered at $ (a,b) $ and of radius $r$ is
$$ (x-a)^2 + (x-b)^2 = r^2 $$

We have the center of the circle, (a,b) = (4,-4), and now as others are suggesting you need the radius.

anonymous · Answer

So r=5

jamesj · Answer

exactly.  Hence the equation of the circle is

(x-4)^2 + (y-(-4))^2 = 5^2.  

Now just clean that up a little.

anonymous · Answer

a=5