Question

Anybody know the right answer?

Answer 1

(x-(-1))^2+(y-(7))^2= 8
to find the center or the values that are placed in the parentheses you find the midpoint of the diameters using the midpoint formula.

`( ( x_(1) + x_(2) )/(2), ( y_(1) + y_(2) )/(2))`
plug in the points

`( ( -3 + 1 )/(2), ( 5 + 9 )/(2)) = (-1,7)`
(-1,7) is the center to plus in to parentheses.
to solve for radis squared plug in one of the endpoints for x and y in the circle equation and the center in the points as well.
circle formula is

`(x-h)^2 +(y-k)^2 = r^2`
plug in and solve for radius squared

`(1-(-1))^2 +(9-(7))^2 = r^2`

`(-2)^2 +(2)^2 = 8 = r^2`
plug in 8 for the radus squared at the end.