Question

How do you find the equation of the circle given r=4; C(3,-4)?

Answer 1

`(x-3)^2+(y+4)^2=16`

Explanation:

The standard form of the equation of a circle is.

`color(red)(|bar(ul(color(white)(a/a)color(black)((x-a)^2+(y-b)^2=r^2)color(white)(a/a)|)))`
where (a ,b) are the coordinates of the centre and r, the radius.

here a = 3 , b = -4 and r = 4

Substitute these values into the standard equation.

`(x-3)^2+(y+4)^2=16" is the equation"`