Question

Write an equation of the circle with center (9,2) and diameter 6.​

Answer 1

`(x - 9)^2 + (y - 2)^2 = 9`

Explanation:

Equation of a circle:

`(x - a)^2 + (y - b)^2 = r^2`

where (a, b) is the center and r is its radius.

First, find the circle's radius:

r = d/2

r = 6/2

r = 3

Finally, construct an equation using the given point and the radius we just solved for:

`(x - 9)^2 + (y - 2)^2 = 3^2`

and simplify to get the answer.

`(x - 9)^2 + (y - 2)^2 = 9`