Question

!!!!GEOMETRY HELP ASAP!!!!
Using the following equation, find the center and radius of the circle. You must show all work and calculations to receive credit.

x2 − 4x + y2 + 8y = −4
I dont understand how to do this))):

Answer 1

Do you know the equation for the center of a circle?

Answer 2

um is it (x-h)2+(y-k)2

Answer 3

You have to complete squares: (a + b)^2 = a^2 + 2ab + b^2

Answer 4

So what do I do??

Answer 5

x^2 − 4x + y^2 + 8y = −4, completing the squares:
(x - 2)^2 = x^2 -4x + 4
(y + 4)^2 = y^2 + 8y + 16, so...

x^2 − 4x + y^2 + 8y = −4
(x-2)^2 - 4 + (y+4)^2 - 16 = -4
(x-2)^2 + (y+4)^2 = 16
(x-2)^2 + (y+4)^2 = 4^2

that means: Center of circle = (2, -4)
Radius = 4

Answer 6

tht ll ame out as like question mark symbols...