document.write( "Question 172691: use the given values to find an equation of the form f(x)= ax^2 + bx + c\r
\n" ); document.write( "\n" ); document.write( "1. f(0)= 5, f(1)=10, f(2)= 19 \r
\n" ); document.write( "\n" ); document.write( "Please explain step by step so I understand!\r
\n" ); document.write( "\n" ); document.write( "I would really appreciate any help!\r
\n" ); document.write( "\n" ); document.write( "Thank you very much
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Algebra.Com's Answer #127548 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
If \"f\" is a function, then \"f%28a%29\" is the value of the function evaluated at \"a\". You are given the values of the function evaluated at 0, 1, and 2. So:\r
\n" ); document.write( "\n" ); document.write( "(1) \"f%280%29=5\" means that \"a%280%29%5E2%2Bb%280%29%2Bc=5\", simplified \"c=5\"\r
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\n" ); document.write( "\n" ); document.write( "(2) \"f%281%29=10\" means that \"a%281%29%5E2%2Bb%281%29%2Bc=10\", simplified \"a%2Bb%2Bc=10\"\r
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\n" ); document.write( "\n" ); document.write( "(3) \"f%282%29=19\" means that \"a%282%29%5E2%2Bb%282%29%2Bc=19\", simplified \"4a%2B2b%2Bc=19\"\r
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\n" ); document.write( "\n" ); document.write( "Since from (1) we have \"c=5\", that can be substituted into (2) and (3), thus:\r
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\n" ); document.write( "\n" ); document.write( "(4) \"a%2Bb%2B5=10\" yielding \"a%2Bb=5\" and,\r
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\n" ); document.write( "\n" ); document.write( "(5) \"4a%2B2b%2B5=19\" yielding \"4a%2B2b=14\" yielding \"2a%2Bb=7\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply (5) by \"-1\":\r
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\n" ); document.write( "\n" ); document.write( "(6) \"-2a-b=-7\"\r
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\n" ); document.write( "\n" ); document.write( "Add (6) to (4) term-by-term:\r
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\n" ); document.write( "\n" ); document.write( "(7) \"-a%2B0b=-2\" or \"a=2\"\r
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\n" ); document.write( "\n" ); document.write( "Substitute \"a=2\" into (4):\r
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\n" ); document.write( "\n" ); document.write( "(8) \"2%2Bb=5\" or \"b=3\"\r
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\n" ); document.write( "\n" ); document.write( "Now you can say that \"f%28x%29=2x%5E2%2B3x%2B5\" by substituting the values determined for \"a\", \"b\", and \"c\" when the system of linear equations was solved.\r
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\n" ); document.write( "\n" ); document.write( "Check:\r
\n" ); document.write( "\n" ); document.write( "\"f%280%29=2%280%29%5E2%2B3%280%29%2B5=0%2B0%2B5=5\" Check\r
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\n" ); document.write( "\n" ); document.write( "\"f%281%29=2%281%29%5E2%2B3%281%29%2B5=2%2B3%2B5=10\" Check\r
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\n" ); document.write( "\n" ); document.write( "\"f%282%29=2%282%29%5E2%2B3%282%29%2B5=8%2B6%2B5=19\" Check
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