Question

what is the equation of a circle centered at the origin and has a radius equal to 10?

Answer 1

The standard form of the equation of a circle is given by:

$\begin{gathered} (x-h)^2+(y-k)^2=r^2 \\ \end{gathered}$

where:

C(h,k) = Center

r = radius

since the circle is centered at the origin and the radius is equal to 10, then:

$\begin{gathered} C(h,k)=(0,0) \\ r=10 \\ (x-0)^2+(y-0)^2=10^2 \\ x^2+y^2=100 \end{gathered}$