Question

The circle below is centered at the point (-3/4) and has a radius of length 3 what is its equation??

Answer 1

{x-(-3/4)}^2=3^2
(x+3/4)^2=9
{(4x+3)/4}^2=9
(4x+3)^2/16=9
(4x+3)^2=9*16
16x^2+2*4x*3+3^2=144
16x^2+24x+9=144
16x^2+24x+9-144=0
16x^2+24x-135=0

Answer 2

`(x+3)^2+(y-4)^2=9`

Explanation:

We are given a circle which is centered at the point (-3,4) and has a radius of length 3.

We have to find the equation of the circle.

The equation of circle centered at (a,b) and radius r is:

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

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

Hence, equation of circle is:

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

`(x+3)^2+(y-4)^2=9`