SOLUTION: what conic section does the following equation represent: 2x^2-8x-y^2-2=0

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Question 83337: what conic section does the following equation represent:
2x^2-8x-y^2-2=0

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!

what conic section does the following equation represent:
2x%5E2-8x-y%5E2-2=0
A hyperbola because it has two squared terms whose coefficients have OPPOSITE SIGNS when on the same side of the equation, they are the terms 2x%5E2 and -y%5E2.
Rule: I will use "square term" to mean either a term in x² or a term in y².
No square terms at all -- a straight line
One square term -- parabola
Two square terms whose coefficients are EQUAL when on the same side of the equation -- circle
Two square terms whose coefficients have the SAME sign when on the same side of the equation -- ellipse (the circle is a special case of the ellipse.)
Two square terms whose coefficients have OPPOSITE SIGNS when on the same side of the equation -- hyperbola.
Edwin