Find the standard form for the equation of a circle

(x−h)^2+(y−k)^2=r^2

with a diameter that has endpoints (−9,−10) and (0,−9).

what are h,k, and r?

Question

Find the standard form for the equation of a circle 

(x−h)^2+(y−k)^2=r^2

with a diameter that has endpoints (−9,−10) and (0,−9). 

what are h,k, and r?

stamp · Answer

Draw a picture. These types of problems are often difficult to solve if you do not have a proper visualization.

anonymous · Answer

ive tried, unsure, please help

tkhunny · Answer

What have you tried?

You have a diameter.  How long is it?  Half of that would be the radius.
You have a diameter.  The middle of it is the center of the circle.

That diameter was AWESOME information.  Don't let it slip away!

stamp · Answer

Here is a circle to start you off! As mentioned, draw your diameter and radius. |dw:1360201652668:dw|

anonymous · Answer

the diameter is the length across the circle, right? how do i incorporate the points

tkhunny · Answer

You're starting to sound a little helpless.  This is actually pretty common when doing geometry and algebra at the same time.

Seriously, though, just draw a diameter and label the two endpoints.  It should be relatively clear after that.