How do you find an equation of the circle with center (2,4) and radius 3?

Question

How do you find an equation of the circle with center (2,4) and radius 3?

1 Answer

Impact of this question

8335 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-12-06T10:05:34

$x^{2} + y^{2} - 4 x - 8 y = - 11$ $x^2+y^2-4x-8y = -11$

Explanation:

If you know the coordinates of the center to be $(x_{0}, y_{0})$ $(x_0,y_0)$ and the radius to be $r$ $r$ , then the equation of the circle with these center and radius is

${(x - x_{0})}_{0}^{2} + {(y - y_{0})}_{0}^{2} = r^{2}$ $(x-x_0)^2 + (y-y_0)^2 = r^2$ .

Plug your values and you have

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

You can either leave the equation as it is, or expand it:

$x^{2} - 4 x + 4 + y^{2} - 8 y + 16 = 9$ $x^2-4x+4 + y^2-8y+16 = 9$

$x^{2} + y^{2} - 4 x - 8 y = - 11$ $x^2+y^2-4x-8y = -11$

Science

Math

Humanities

... and beyond

How do you find an equation of the circle with center (2,4) and radius 3?

1 Answer

Explanation:

Related questions

Impact of this question