SOLUTION: PLEASE HELP!!! IM SO CONFUSED!!! Thank you! Write the standard equation of this conic section: y^2-x^2+2y-14x-57

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Question 606785: PLEASE HELP!!! IM SO CONFUSED!!! Thank you!
Write the standard equation of this conic section:
y^2-x^2+2y-14x-57

Found 3 solutions by lwsshak3, ewatrrr, josmiceli:
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Write the standard equation of this conic section:
y^2-x^2+2y-14x-57=0
complete the square
(y^2+2y+1)-(x^2+14x+49)=57+1-49
(y+1)^2-(x+7)^2=9
(y+1)^2/9-(x+7)^2/9=1
This is an equation of a hyperbola with vertical transverse axis.
Its standard form of equation: (y-k)^2/a^2-(x-h)^2=1, (h,k)=(x,y) coordinates of center.
For given equation:
center: (-7,-1)
a^2=9
b^2=9

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 
Hi,
Write the standard equation of this conic section:
y^2-x^2+2y-14x-57
(y^2+2y+1)-1 -(x^2+14x+49)+ 49 - 57 = 0
(y+1)^2 - (x+7)^2 = 9
Standard Form:
%28y%2B1%29%5E2+%2F9+-+%28x%2B7%29%5E2%2F9+=+1
Standard Form of an Equation of an Hyperbola opening up and down is:
%28y-k%29%5E2%2Fb%5E2+-+%28x-h%29%5E2%2Fa%5E2+=+1 where Pt(h,k) is a center with vertices 'b' units up and down from center.


Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Actually, you didn't give me an equation, so
I can't give you an equation. You need an "="
sign somewhere, so I'll assume you have
+y%5E2+-+x%5E2+%2B+2y+-+14x+-+57+=+0+
------------
Add +57+ to both sides
+y%5E2+-+x%5E2+%2B+2y+-+14x+=+57+
Rearrange the terms on the left
+y%5E2+%2B+2y+-+x%5E2+-+14x+=+57+
Complete the square for the y terms and the x terms

+%28+y%5E2+%2B+2y+%2B+1+%29+-+%28+x%5E2+%2B+14x+%2B+49+%29+=+57+%2B+1+-+49+
+%28+y+%2B+1+%29%5E2+-+%28+x+%2B+7+%29%5E2+=+9+
Divide both sides by +9+
+%28+y+%2B+1+%29%5E2%2F+3%5E2+-+%28+x+%2B+7+%29%5E2%2F+3%5E2+=+1+
This is a hyperbola with center at (-7,-1)