document.write( "Question 464984: I am taking integrated algebra online, and my teacher gave us two standard equations for a parabola in the conic section, but she failed to explain how we decide which one to use when given a problem like \"focus (-2,1)and directrix x = 3\". the two equations she gave us are the vertical equation \"(x - h)^2 = 4p (y - k)\" and the horizontal equation \"(y - k)^2 = 4p (x - h) i know how to figure out what h, k, and p are but she didn't explain how we are suppose to determine which equation to plug our answers into. The two equations give you two different answers when you figure the problem out. \n" ); document.write( "

Algebra.Com's Answer #318584 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Your given directrix is a vertical line (

), that means you should use the form that has the

variable squared. If the directrix is horizontal (

), then use the form with the

variable squared.\r
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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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$\"The$

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