This circle is centered at the origin, and the length of its radius is 3. What is the equation of the circle?
(Picture attached)

A. x^2 +y^2=3^2

B. x^2 y^2
____+____=1
3^2 3^2

C. x^2+y^2=4

D.(x-3)^2+(y-3)^2=16

Question

This circle is centered at the origin, and the length of its radius is 3. What is the equation of the circle?
(Picture attached)

A. x^2 +y^2=3^2

B. x^2  y^2
   ____+____=1
   3^2    3^2

C. x^2+y^2=4

D.(x-3)^2+(y-3)^2=16

anonymous · Answer

attachment

anonymous · Answer

I'm thinking the answer is D.(x-3)^2+(y-3)^2=16? am i right ?

anonymous · Answer

or A?

darkprince14 · Answer

Do you know the formula of a circle?

anonymous · Answer

no i dont

darkprince14 · Answer

This is the formula of a circle with center (h,k)...

Plug in the coordinates of the center which is (0, 0)
As well as r
You'll get the answer...

darkprince14 · Answer

(x-h)^2 + (y-k)^2 = r^2

darkprince14 · Answer

sorry..my net connection is kinda crappy..

darkprince14 · Answer

h = 0
k = 0
r = 3

anonymous · Answer

i got a the first time and d the second

darkprince14 · Answer

how'd you got d?

anonymous · Answer

i multiplied the radious but i wasnt using the correct formula

anonymous · Answer

so A is the answer! right?

darkprince14 · Answer

yes...

For circle's whose center is at the origin, you only have to plug in the length of the radius in the formula x^2 + y^2 = r^2