document.write( "Question 618930: Does this parabola open upward or downward? How do you know?\r
\n" ); document.write( "\n" ); document.write( "y=x^2-1 \n" ); document.write( "

Algebra.Com's Answer #389212 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Upward, because the sign of the $\"+x%5E2+\"$ term
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\n" ); document.write( "here's the plot of $\"+y+=+x%5E2+-+1+\"$
\n" ); document.write( " $\"+graph%28+400%2C+400%2C+-5%2C+5%2C+-2%2C+6%2C+x%5E2+-+1+%29+\"$
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\n" ); document.write( "Here's the plot of $\"+y+=+-x%5E2+-+1+\"$
\n" ); document.write( " $\"+graph%28+400%2C+400%2C+-5%2C+5%2C+-6%2C+2%2C+-x%5E2+-+1+%29+\"$ \n" ); document.write( "

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