Question

complete the square to find the center and radius of the circle whose equation is x^2 + y^2 -4y = 36

Answer 1

@dan815

Answer 2

help meee

Answer 3

okay!! complete the square!

Answer 4

complete the square for the y part
x^2 + y^2 -4y = 36
x^2+(y+a)^2 -a^2 = 36
what does a have to be?

Answer 5

x^2 + y^2 -4y = 36

x^2+(y+a)^2 -a^2 = 36; if i expand this out i get...

x^2+ y^2+2ay +a^2-a^2=36

http://prntscr.com/700a09 , as the rest is all equal



y^2+2ay +a^2-a^2 = y^2 -4y
a=-2

Answer 6

questions concerns??!

Answer 7

I think I got it. Thanks!