Question

How do you find an equation of the circle whose center is (-3,1) and whose radius is 8?

Answer 1

`(x+3)^2+(y-1)^2=64`

Explanation:

`"the equation of a circle in standard form is"`

`color(red)(bar(ul|color(white)(2/2)color(black)((x-a)^2+(y-b)^2=r^2)color(white)(2/2)|))`

`"where "(a,b)" are the coordinates of the centre and r"`
`"is the radius"`

`"here "(a,b)=(-3,1)" and "r=8`

`(x-(-3))^2+(y-1)^2=8^2`

`rArr(x+3)^2+(y-1)^2=64larrcolor(red)"equation of circle"`