document.write( "Question 709270: y=-3x^2-9x-12 need help finding the vertex and axis \n" ); document.write( "
Algebra.Com's Answer #436476 by josgarithmetic(39838)\"\" \"About 
You can put this solution on YOUR website!
EDIT: Fixed the sign mistake.\r
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\n" ); document.write( "\n" ); document.write( "First, factor. Then complete the square.\r
\n" ); document.write( "\n" ); document.write( "\"y=-3%28x%5E2%2B3x%2B4%29\"
\n" ); document.write( "The square to add and subtract is \"%283%2F2%29%5E2\".\r
\n" ); document.write( "\n" ); document.write( "\"y=-3%28x%5E2%2B3x%2B%283%2F2%29%5E2+%2B4-%283%2F2%29%5E2%29\"
\n" ); document.write( "\"y=-3%28%28x%2B%283%2F2%29%29%5E2%2B%287%2F4%29%29\"
\n" ); document.write( "\"y=-3%28x%2B3%2F2%29%5E2%2B7%2F4\"
\n" ); document.write( "\"y=-3%28x%2B3%2F2%29%5E2-21%2F4\"
\n" ); document.write( "\"y=-3%28x%2B3%2F2%29%5E2-5%261%2F4%29\"\r
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\n" ); document.write( "\n" ); document.write( "The value of \"h\" is \"-%283%2F2%29\" and the value of \"k\" is \"-%2821%2F4%29\" or \"-%285%261%2F4%29\".
\n" ); document.write( "The vertex is (\"-%283%2F2%29\",\"-5%261%2F4\")
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