Question

The circle below is centered at the origin and has a radius of 4. What is its

equation?
OA. x^2 - y^2=16
OB.x²+ y^2=4
OC. x²+y^2=16
OD. x²- y²=4

Answer 1

option C:

x² + y² = 16

Explanation:

general equation of a circle is,

(x - h)² + (y - k)² = r²

where (h, k) are the coordinates of the center of the circle

r is the radius of the circle

according to the question the circle is centered at the origin so h and k will be 0

and r = 4

by substituting the values in the equation,

(x - 0)² + (y - 0)² = 4²

x² + y² = 16

Answer 2

C)
`x^2+y^2=16`

Explanation:

`(x-h)^2+(y-k)^2=r^2\\(x-0)^2+(y-0)^2=4^2\\x^2+y^2=16`

Therefore, C is correct