Question

a circle has its center at (-5,4) and a radius of 3 units. what is the equation of the circle?

Answer 1

$\bf \textit{equation of a circle}\\\\ (x- h)^2+(y- k)^2= r^2 \qquad center~~(\stackrel{-5}{ h},\stackrel{4}{ k})\qquad \qquad radius=\stackrel{3}{ r} \\\\\\\ [x-(-5)]^2+[y-4]^2=3^2\implies (x+5)^2+(y-4)^2=9$