Question

find the center (h,k) and radius r of the circle with the given equation
x^2+y^2-4x+18y+85=36

Answer 1

do u know how to complete the square ?

Answer 2

(x^2-4x)(y^2+18y)

Answer 3

not like that
x^2 - 4x + ... = (x- ....)^2
?

Answer 4

okay still lost

Answer 5

ok, what will u add to x^2-4x to make it a perfect square
of the form
(x-h)^2.

Answer 6

(x-2)(x+2)?

Answer 7

no, wait, i'll tell you step by step
1) tell me what is the co-efficient of x ?

Answer 8

4?

Answer 9

yesm now divide it by 2, what u get ?

Answer 10

2

Answer 11

now square it, and add it to x^2-4x
what get ?

Answer 12

not sure