How do you find the area $(x - 2 )² + (y + 4 )² = 9$ ?

Question

5882 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-02-05T15:21:01

The area of the circle described by your equation is $9 pi " units"^2 ~~ 28.27 " units"^2$ .

The equation

$(x-2)^2 + (y + 4)^2 = 9$

describes a circle.

A standard circle equation for a circle with the center $(h, k)$ and the radius $r$ has the form

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

Thus, in your case, the center of your circle is the point $(2, -4)$ and your radius is $3$ .

If I understand your question correctly, you would like to compute the area of this circle.

The formula for that is

$A = pi r^2 = pi * 3^2 = 9pi ~~ 28.27 " units"^2$

How do you find the area (x - 2 )² + (y + 4 )² = 9(x - 2 )² + (y + 4 )² = 9?