document.write( "Question 530867: If the vertex of a parabola is (-1,-7) how can I find the equation of the parabola? Is this possible? \n" ); document.write( "

Algebra.Com's Answer #350229 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Not quite, the x-coordinate of the vertex is
\n" ); document.write( " $\"+-b%2F%282a%29+\"$ when the general formula
\n" ); document.write( "for the equation is $\"+y+=+ax%5E2+%2B+bx+%2B+c+\"$
\n" ); document.write( "So I have:
\n" ); document.write( " $\"+-b%2F%282a%29+=+-1+\"$
\n" ); document.write( " $\"+b+=+2a+\"$
\n" ); document.write( "the y coordinate is $\"+-7+\"$ , so
\n" ); document.write( " $\"+-7+=+a%2Ax%5E2+%2B+2a%2Ax+%2B+c+\"$
\n" ); document.write( " $\"+a%2Ax%5E2+%2B+2a%2Ax+%2B+c+%2B+7+=+0+\"$
\n" ); document.write( "I can still only get a formula for the roots in terms
\n" ); document.write( "of $\"a\"$ and $\"c\"$ , so there can be many equations
\n" ); document.write( "that have (-1,-7) for a vertex \n" ); document.write( "

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