document.write( "Question 1206103: Find an equation in the form y=ax^2+bx+c for the parabola passing through the points (-1,0),(2,-54),(5,-252) \n" ); document.write( "
Algebra.Com's Answer #843330 by MathLover1(20849)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"y=ax%5E2%2Bbx%2Bc\"\r
\n" ); document.write( "\n" ); document.write( "given:
\n" ); document.write( "(\"-1\",\"0\"),(\"2\",\"-54\"),(\"5\",\"-252\")\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "use (\"-1\",\"0\")\r
\n" ); document.write( "\n" ); document.write( "\"0=a%28-1%29%5E2%2Bb%28-1%29%2Bc\"
\n" ); document.write( "\"a-b%2Bc=0\".......eq.1\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "use (\"2\",\"-54\")\r
\n" ); document.write( "\n" ); document.write( "\"-54=a%282%29%5E2%2Bb%282%29%2Bc\"
\n" ); document.write( "\"-54=4a%2B2b%2Bc\"
\n" ); document.write( "\"4a%2B2b%2Bc=-54\".......eq.2\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "use (\"5\",\"-252\")\r
\n" ); document.write( "\n" ); document.write( "\"-252=a%285%29%5E2%2Bb%285%29%2Bc\"
\n" ); document.write( "\"-252=25a%2B5b%2Bc\"
\n" ); document.write( "\"25a%2B5b%2Bc=-252\".......eq.3\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "solve the system:\r
\n" ); document.write( "\n" ); document.write( "\"a-b%2Bc=0\".......eq.1
\n" ); document.write( "\"4a%2B2b%2Bc=-54\".......eq.2
\n" ); document.write( "\"25a%2B5b%2Bc=-252\".......eq.3
\n" ); document.write( "_________________________\r
\n" ); document.write( "\n" ); document.write( " subtract eq.1 from eq.2\r
\n" ); document.write( "\n" ); document.write( "\"4a%2B2b%2Bc-%28a-b%2Bc%29=-54-0\"
\n" ); document.write( "\"4a%2B2b%2Bc-a%2Bb-c=-54\"
\n" ); document.write( "\"3a%2B3b=-54\"
\n" ); document.write( "\"a%2Bb=-54%2F3\"
\n" ); document.write( "\"a%2Bb=-18\"
\n" ); document.write( "\"a=-b-18\".....eq.1a\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "go to\r
\n" ); document.write( "\n" ); document.write( "\"a-b%2Bc=0\".......eq.1, substitute \"a\"
\n" ); document.write( "\"-b-18-b%2Bc=0\"
\n" ); document.write( "\"-2b%2Bc=18\"
\n" ); document.write( "\"c=2b%2B18\"....eq.2a\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "go to\r
\n" ); document.write( "\n" ); document.write( "\"25a%2B5b%2Bc=-252\".......eq.3, substitute \"a\" and \"c\"
\n" ); document.write( "\"25%28-b-18%29%2B5b%2B2b%2B18=-252\"
\n" ); document.write( "\"25%28-b-18%29%2B5b%2B2b%2B18=-252\"
\n" ); document.write( "\"-18b+-+432=-252\"
\n" ); document.write( "\"252-432=18b\"
\n" ); document.write( "\"-180=18b\"
\n" ); document.write( "\"b=-10\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "go to\r
\n" ); document.write( "\n" ); document.write( "\"a=-b-18\".....eq.1a, substitute \"b\"
\n" ); document.write( "\"a=-%28-10%29-18\"
\n" ); document.write( "\"a=10-18\"
\n" ); document.write( "\"a=-8\"\r
\n" ); document.write( "\n" ); document.write( "go to\r
\n" ); document.write( "\n" ); document.write( "\"c=2b%2B18\"....eq.2a, substitute \"b\"
\n" ); document.write( "\"c=2%28-10%29%2B18\"
\n" ); document.write( "\"c=-20%2B18\"
\n" ); document.write( "\"c=-2\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "your equation is:\r
\n" ); document.write( "\n" ); document.write( "\"y=-8x%5E2-10x-2\"\r
\n" ); document.write( "\n" ); document.write( "
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