document.write( "Question 982450: hi i need help with the following\r
\n" ); document.write( "\n" ); document.write( "Given f(x)=ax^2+b and f(2)=5, f(3)=20, find a and b\r
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Algebra.Com's Answer #603267 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
First focus on f(2) = 5\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29=ax%5E2%2Bb\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%282%29=a%282%29%5E2%2Bb\" Plug in x = 2\r
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\n" ); document.write( "\n" ); document.write( "\"f%282%29=4a%2Bb\"\r
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\n" ); document.write( "\n" ); document.write( "\"5=4a%2Bb\" Replace f(2) with 5\r
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\n" ); document.write( "\n" ); document.write( "\"5-4a=b\"\r
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\n" ); document.write( "\n" ); document.write( "\"b=5-4a\"\r
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\n" ); document.write( "\n" ); document.write( "Now move onto f(3) = 20\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29=ax%5E2%2Bb\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%283%29=a%283%29%5E2%2Bb\" Replace every x with 3\r
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\n" ); document.write( "\n" ); document.write( "\"f%283%29=9a%2Bb\"\r
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\n" ); document.write( "\n" ); document.write( "\"20=9a%2Bb\" Replace f(3) with 20\r
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\n" ); document.write( "\n" ); document.write( "\"20=9a%2B5-4a\" Replace b with 5-4a\r
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\n" ); document.write( "\n" ); document.write( "I'll let you finish up. The goal is to isolate 'a'. Once you know the value of 'a', you plug it into \"b=5-4a\" to find the value of 'b'.
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