document.write( "Question 810496: Can you please help me solve this question determine in a hand calculation the parabola with focus (o,o) and directrix x+y+1=0. what is its vertex? plot the parabola indicating vertex, focus and directrix. thank you \n" ); document.write( "
Algebra.Com's Answer #488208 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "The green line is the directrix x+y+1 = 0\r\n" );
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document.write( "The vertex V is half-way between the focus and the directrix on\r\n" );
document.write( "a perpendicular from the focus to the directrix, the blue line\r\n" );
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document.write( "Draw perpendiculars from the end of that blue line and from \r\n" );
document.write( "the vertex V to the x-axis:\r\n" );
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document.write( "Now with a little bit of geometry knowledge, it's easy to \r\n" );
document.write( "see that the vertex is \"%28matrix%281%2C3%2C-1%2F4%2C%22%2C%22%2C-1%2F4%29%29\"\r\n" );
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document.write( "Edwin
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