document.write( "Question 857859: Find the vertex, focus and directrix of the parabola given by the equaiton (y + 2)^2 + -4(x-1) \n" ); document.write( "

Algebra.Com's Answer #516984 by KMST(5328) $\"\"$ $\"About$

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You are missing something. There should be an equal sign somewhere.
\n" ); document.write( "Maybe you meant to type
\n" ); document.write( "(y + 2)^2 = -4(x-1) and got a + sign instead of the intended = sign.
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\n" ); document.write( " $\"%28y+%2B+2%29%5E2+=+-4%28x-1%29\"$ <--> $\"-%281%2F4%29%28y+%2B+2%29%5E2+=+%28x-1%29\"$
\n" ); document.write( "is the equation of a parabola with a horizontal axis of symmetry,
\n" ); document.write( " $\"y%2B2=0\"$ <--> $\"y=-2\"$ ,
\n" ); document.write( "and the vertex at (1,-2).
\n" ); document.write( "The focal distance is $\"1\"$ ,
\n" ); document.write( "and the focus and the rest of the parabola are to the left.
\n" ); document.write( "So the focus is at (0,-2),
\n" ); document.write( " $\"1\"$ unit to the left of (1,-2),
\n" ); document.write( "and the directrix is the line $\"x=2\"$ ,
\n" ); document.write( " $\"1\"$ unit to the left of (1,-2).
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