Question

HELP


Find the radius of the circle whose equation is (x + 5)² + (y + 8)² = 16 4 16 256

Answer 1

The radius is the square root of 16. So 4. 

Answer 2

$\bf \textit{equation of a circle}\\\\ (x- h)^2+(y- k)^2= r^2 \qquad center~~(\stackrel{}{ h},\stackrel{}{ k})\qquad \qquad radius=\stackrel{}{ \boxed{r}}\\\\ -------------------------------\\\\ (x+5)^2+(y+8)^2=16\implies (x+5)^2+(y+8)^2=\boxed{4}^2$