Question

Could somebody please help me solve this?

Answer 1

A. `15` units
B. `(-12,-3)`

Explanation:

This equation is in the form `(x-h)^2+(y-k)^2=r^2` where `(h,k)` are the coordinates of the center of the circle and `r` is the radius of the circle. Therefore, for A:

`r^2=225` Square root both sides:
`r=+-15` Distance cannot be negative, so:
A. `r=15` units

For B:
`(h,k)` equals
B. `(-12,-3)` using the form above.

Answer 2

The equation of a circle is given by `(x−a)^2+(y−b)^2=r^2`,
where`r` is the radius, and (a,b) are the coordinates of the center.

Therefore, comparing the corresponding terms,

`r^2 = 225`
`=>"Radius ", r = sqrt225 =15" units"`

and,
`"Centre would be at "O=(−12,-3)`