SOLUTION: Find the standard form of the equation for the circle with center at (-3, -1) and diameter of 2 sqrt 5.

Question 1087913: Find the standard form of the equation for the circle with center at (-3, -1) and diameter of 2 sqrt 5.
Found 2 solutions by solver91311, ikleyn:
Answer by solver91311(24713)   (Show Source): You can put this solution on YOUR website!

The standard form of an equation of a circle is:

Where are the coordinates of the center and is the radius. Note that you have to retain the minus sign that is given in the formula when you substitute a negative number for either h or k. Hence, you end up with x plus something and/or y plus something if either h or k is negative. Don't forget to square r.

John

My calculator said it, I believe it, that settles it

Answer by ikleyn(52802)   (Show Source): You can put this solution on YOUR website!
.
= ,

or, which is the same,

= 20.

See the lessons
    - Standard equation of a circle
    - Find the standard equation of a circle
in this site.

RELATED QUESTIONS
For A and B, find the standard form of the equation of each circle. A. With... (answered by Edwin McCravy)
1. find the equation of the circle in standard form with center at ( -2, 1) and passing... (answered by mouk)
find the equation, in standard form, of the circle being described in each item.... (answered by mathmate)
Find the standard form of the equation of the circle with the given radius and center. (answered by Alan3354)
Find the equation of the circle (standard form) with center at (3,-4) and passing through (answered by Alan3354)
1. Write the following equation of a circle in standard form: x^2+y^2-4x +2y+3=0 2.... (answered by solver91311)
Determine a polar equation for the circle with a radius of sqrt(5) and a center at... (answered by Edwin McCravy)
Find the equation, in standard form, of the circle. Diameter with endpoints (-2,-1) and... (answered by josgarithmetic,ikleyn,MathTherapy)
Write the standard form of the equation of the circle with center at (2, -7)and radius... (answered by josgarithmetic,Edwin McCravy)