Question
Find standard equation of a circle with a center at $ \color{blue}{C = \left( 7 , 0 \right)} $ and radius $ \color{blue}{ 3 }$
Answer
The circle equation is:
$$ \color{blue}{ \left(x - 7 \right)^2 + y^2 = 9 }$$Explanation
The equation of a circle with center at $(\color{blue}{h} , \color{red}{k})$ and a radius of $ r $ is:
$$ (x - \color{blue}{h} )^2 + (y - \color{red}{k})^2 = r^2 $$In this example $ \color{blue}{h = 7 } $, $ \color{red}{k = 0 }$ and $ r = 3 $, so after substituting into above formula we have:
$$ \begin{aligned} \left(x - 7 \right)^2 + \left(y - 0 \right)^2 &= 3^2 \\ \left(x - 7 \right)^2 + y^2 &= 9 \end{aligned} $$This page was created using
Circle equation Calculator