Question

The center of a circle and a point on the circle are given. Write the equationcenter: (3,-2), point on the circle: (-1,4)

Answer 1

With the center and one point of the circle we can calculate the radius so:

$\begin{gathered} r=\sqrt[]{(3-(-1))^2+(-2-4)^2} \\ r=\sqrt[]{4^2+6^2} \\ r=\sqrt[]{16+36} \\ r=\sqrt[]{52} \\ r^2=52 \end{gathered}$

now we know that the radius of a circle is:

$52^2=(x-3)^2+(y+2)^2$