document.write( "Question 1097586: how do you know if a parabola opens up or down? \n" ); document.write( "

Algebra.Com's Answer #712029 by josgarithmetic(39617) $\"\"$ $\"About$

You can put this solution on YOUR website!
You just look at the graph (since you know you have a parabola and are looking at it already) and either the vertex is at the bottom or it is at the top. If on the bottom, parabola opens UP. If vertex at the top then parabola opens DOWN. You just SEE it.\r
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\n" ); document.write( "\n" ); document.write( "THIS IS WHAT YOU WANT:\r
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\n" ); document.write( "\n" ); document.write( "If you have no given graph but do have an equation or the function, then\r
\n" ); document.write( "\n" ); document.write( " $\"y=ax%5E2%2Bbx%2Bc\"$
\n" ); document.write( "and if $\"a%3C0\"$ , the parabola opens DOWNWARD.
\n" ); document.write( "If $\"a%3E0\"$ , then parabola opens UPWARD. \n" ); document.write( "

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