Question

Classify the graph of the eq

9x^2+25y^2-54x+250y+481=0

Answer 1

I know it's an ellipse, but I have to turn it into the proper form. What I want to know is how do I find h and k, or what shall I do?

Answer 2

@asnaseer @TuringTest @lgbasallote :)

Answer 3

have you tried completing the square?

Answer 4

yup

Answer 5

http://www.wolframalpha.com/input/?i=9x^2%2B25y^2-54x%2B250y%2B481%3D0

Answer 6

I tried to split it up into (9x^2 - 54x) and (25y^2+250y+500)-19 and a few others, but couldn't complete the square with y...

Answer 7

I know viper, I need to prove that it's an ellipse, so I need to get it into proper form.

Answer 8

9x^2+25y^2-54x+250y+481=0

transpose 481

9x^2 + 25y^2 -54x + 250y = -481

now do completing the square

9x^2 - 54x + 25y^2 + 250y = -481

9(x^2 - 6x) + 25(y^2 + 10y) = -481

9(x^2 - 6x + 9) + 25(y^2 + 10y + 25) = -481+ 81 + 625

9(x-3)^2 + 25(y + 5)^2 = 225

divide everything by 225...

\[\frac{(x-3)^2}{25} + \frac{(y+5)^2}{9} = 1\]
does that help?

Answer 9

@KonradZuse walked out on me again :'C

Answer 10

Dude this site keeps crashing on me haha...

Answer 11

It just logged me out :(.

Answer 12

haha lol

Answer 13

interesting how you solved this, thanks iggy :).

Answer 14

ok I got another one that's a hyperbola...

x^2-4y^2-2x-16y-31=0

Answer 15

(X^2-2x) - (4y^2-16y) = 31

Answer 16

+16y

Answer 17

and honestly..i had no idea what i was doing...im weak in graphs....it was just a fluke..i was hoping it would come out right in the end =)))

Answer 18

(x^2-2x + 1) - 4(y^2+4y +4) = 31 -1 -16

Answer 19

LOL dude don't tell me that :(

Answer 20

should be 31+1

Answer 21

@TuringTest what is he doijng to me?

Answer 22

+1? Isn't it +1 on the other side?

Answer 23

lol it was right

Answer 24

oh wait derp.

Answer 25

lol what are you saying

Answer 26

+16 also then....

Answer 27

nope

Answer 28

it's -16

Answer 29

-4 x 4 = -16

Answer 30

cuz of the neg in front?

Answer 31

I gues ssooo..

Answer 32

wiat....

Answer 33

so it's now (x-1)^2 -4(y+2) = 16

Answer 34

something smells wrong here

Answer 35

I blamr you dude...

Answer 36

lol

Answer 37

i did the ellipse right :p

Answer 38

:)

Answer 39

anyway i'll be right back..i'll help if it wasnt solved by the time i get back

Answer 40

isn't it just going to be (x-1)^2/16 - (y+2)^2/4 = 1?

Answer 41

fyi, here is its plot
http://www.wolframalpha.com/input/?i=%28x-1%29%5E2%2F16+-+%28y%2B2%29%5E2%2F4+%3D+1

Answer 42

look the same to me, thanks :)

Answer 43

lol yeah...guess i didnt see that one...good one @KonradZuse

Answer 44

yeah iggy!!!! :)