SOLUTION: Identify the conic (circle, ellipse, or hyperbola) and state the center 2x^2-y^2+2x+10y-41=0

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Question 81934: Identify the conic (circle, ellipse, or hyperbola) and state the center
2x^2-y^2+2x+10y-41=0

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
2+%2A+x+%5E+2+-+y+%5E+2+%2B+2+%2A+x+%2B+1+0+%2A+y+-+4+1++++=0 Start with the given conic



2+%2A+x+%5E+2+-+y+%5E+2+%2B+2+%2A+x+%2B+1+0+%2A+y+=+4+1+++Add 41 to both sides



%28+2+%2A+x+%5E+2+%2B+2+%2A+x+%29+%2B+%28+-+y+%5E+2+%2B+1+0+%2A+y+%29+=+4+1++ Group like terms




2+%28+x+%5E+2+%2B+x+%29+-+1+%28+y+%5E+2+-+1+0+%2A+y+%29+=+4+1++++ Factor a 2 out of the first parenthesis
and factor a -1 out of the second parenthesis.




Now we must complete the individual squares inside the parenthesis:



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For instance to complete 2+%28+x+%5E+2+%2B+x+%29++, take half of 1 and square it (ie %281%2F2%29%5E2=%280.5%29%5E2=0.25 to get 0.25. Now add 0.25 inside the parenthesis like this:
2+%28+x+%5E+2+%2B+x+%2B+0+.+2+5+%29++
Since you really added 2%2A0.25 to the entire left side, we must add 2%2A0.25 to the right side also. Now lets complete -+1+%28+y+%5E+2+-+1+0+%2A+y+%29+

In order to complete -+1+%28+y+%5E+2+-+1+0+%2A+y+%29+, take half of -10 and square it (ie %28-10%2F2%29%5E2=%28-5%29%5E2=25 to get 25. Now add 25 inside the parenthesis like this:
-+1+%28+y+%5E+2+-+1+0+%2A+y+%2B+2+5+%29+
Since you really added -1%2A25 to the entire left side, we must add -1%2A25 to the right side also.

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Complete the individual squares by taking half of the 2nd coefficient and squaring it (remember to add to both sides).

2+%28+x+%5E+2+%2B+x+%2B+0+.+2+5+%29+-+1+%28+y+%5E+2+-+1+0+%2A+y+%2B+2+5+%29+=+1+6+.+5++++ Combine like terms on the right side




2+%28+x+%2B+0+.+5+%29+%5E+2+-+1+%28+y+-+5+%29+%5E+2+=+1+6+.+5++ Factor the individual groups on the left side

Divide both sides by 16.5




1+%28+x+%2B+0+.+5+%29+%5E+2+%2F+8+.+2+5+%2B+1+%28+y+-+5+%29+%5E+2+%2F+-+1+6+.+5+=+1+ Break up the fraction into standard form %28x-h%29%5E2%2Fa%5E2%2B%28y-k%29%5E2%2Fb%5E2=1
So the equation is a hyperbola where the center is (-0.5,5)

From the graph, you can see the center (blue dot)



Here's the graph of 1+%28+x+%2B+0+.+5+%29+%5E+2+%2F+8+.+2+5+%2B+1+%28+y+-+5+%29+%5E+2+%2F+-+1+6+.+5+=+1+
note: the straight lines are not part of the graph. They are the asymptotes with slopes of ±b%2Fa.

Here is a check/verification graph of 2+%2A+x+%5E+2+-+y+%5E+2+%2B+2+%2A+x+%2B+1+0+%2A+y+-+4+1++++=0