Question

Write an equation if a circle has a center of (3,-1) and the diameter 8

Answer 1

`(x-3)^2+(y+1)^2=16`

Step-by-step explanation:

The equation of a circle with center (h, k) and radius of r is generally given as;

`(x-h)^2+(y-k)^2=r^2`

Given the center of the circle as (3, -1) and the diameter of 8 (r = d/2 = 8/2 = 4), the equation of the circle can then be written as shown below;

`\begin{gathered} (x-3)^2+\lbrack y-(-1)\rbrack^2=4^2 \\ (x-3)^2+(y+1)^2=16 \end{gathered}`