geometry
posted by lindsay on .
Find the coordinates of the center and the radius of a circle with and equation of:
a. x^2 + 2root7x +7 + (Yroot 11)^2 =11
b. x^2 12x + 84 =y^2 + 16y

a. Clarify Eq.
b. x^212x=84 y^2+16y.
x^212x+(12/2)^2+y^216y+(16/2)^2 = 84+36+64.
x^212x+36+y^216y+(16/2)^2 = 84.
x^212x+36+y^216y+64 = 84+36+64.
(x6)^2+(y8)^2 = 16.
C(6.8).
r^2 = 16.
r = 4.