Question

Which of the following equations correctly represents a circle centered at the

origin with a radius of 7?

Answer 1

C

Explanation:

Hopefully this helps :)

Answer 2

Answer:
`x^2+y^2=7^2` (C)

Explanation:

Alright, lets get started.

The standard equation of a circle is given by :

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

Where (h,k) is the center of circle and r is the radius of circle.

As per given question, center should be origin, it means the center should be
`(h,k)=(0,0)`

As per given question, radius should be 7, it means
`r=7`

Plugging the value of (h,k) and r in standard equation of circle,

`(x-0)^2+(y-0)^2=7^2`

`x^2+y^2=7^2` ...... Answer (C)

Hope it will help :)