What is its Equation?

Question

The circle below is centered at the point (-2,1) and has a radius of length 3. what is its equation?

Answer 1

center (-2,1) and radius 3

 

(x-h)²+(y-k)²=r² with center (h,k) and radius r

(x+2)²+(y-1)²=3²

(x+2)²+(y-1)²=9

Answer 2

The equation of any circle is

 

(x - h)² + (y - k)² = r²

 

where:

(h, k) is the circle centerpoint

r is the radius

Answer 3

Hi there,

 

Since you are given the center and radius of the circle, you can write the equation in center -radius form 

 

(x-h)² + ( y-k)² = r²

 

where : ( h,k) is the center and r is the radius

 

in your problem h = -2  , k = 1 and r= 3

 

just plug these values into the equation: just be careful with the value of h , it is = to -2 

 

(x - -2) + (y-1) = 3²

   (x+2) + (y-1) = 9

 

Hope it helps.