document.write( "Question 64721: find the vertex of the parabola: x^2 + 4x + 8y - 20 =0 \n" ); document.write( "

Algebra.Com's Answer #45260 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"x%5E2+%2B+4x+%2B+8y+-+20+=+0\"$
\n" ); document.write( "first put this in the form
\n" ); document.write( " $\"y+=+ax%5E2+%2B+bx+%2B+c\"$
\n" ); document.write( "The vertex is at ( $\"%28-b%29+%2F+2a\"$ , $\"y\"$ )
\n" ); document.write( " $\"-8y+=+x%5E2+%2B+4x+-+20\"$
\n" ); document.write( " $\"y+=+%28-1%2F8%29x%5E2+%2B+4x%2F%28-8%29+-20+%2F+%28-8%29\"$
\n" ); document.write( " $\"%28-b%29+%2F+2a+=+%281%2F2%29+%2F+%28-1%2F4%29\"$
\n" ); document.write( " $\"%28-b%29+%2F+2a+=+-2\"$
\n" ); document.write( "solve for y
\n" ); document.write( " $\"x%5E2+%2B+4x+%2B+8y+-+20+=+0\"$
\n" ); document.write( " $\"%28-2%29%5E2+%2B+4%28-2%29+%2B+8y+-+20+=+0\"$
\n" ); document.write( " $\"4+-+8+%2B+8y+-+20+=+0\"$
\n" ); document.write( " $\"8y+=+24\"$
\n" ); document.write( " $\"y+=+3\"$
\n" ); document.write( "The vertex is at (-2 , 3) \n" ); document.write( "

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