document.write( "Question 1080078: How do you find real numbers a,b and c so that the graph of the function \"+y=ax%5E2%2Bbx%2Bc+\" contains the points (-1,5), (3,8) and (0,2)?\r
\n" ); document.write( "\n" ); document.write( "My process went as\r
\n" ); document.write( "\n" ); document.write( " (-1,5) is a point on the graph then values are, x=-1 and y=5 that must satisfy y=ax^2+bx+c
\n" ); document.write( "Equation one being \"+a%28-1%29%5E2%2Bb%28-1%29%2Bc=5+\"\r
\n" ); document.write( "\n" ); document.write( " (3,8) is a point on the graph then values are, x=3 and y=8 that must satisfy y=ax^2+bx+c
\n" ); document.write( "Equation two being \"+a%283%29%5E2%2Bb%283%29%2Bc=8+\"\r
\n" ); document.write( "\n" ); document.write( " (0,2) is a point on the graph then values are, x=0 and y=2 that must satisfy y=ax^2+bx+c
\n" ); document.write( "Equation three being \"+a%280%29%5E2%2Bb%280%29%2Bc=2+\"\r
\n" ); document.write( "\n" ); document.write( "that gives the system of 3 equation which are
\n" ); document.write( "ONE \"+a-b%2Bc=5+\"
\n" ); document.write( "TWO \"+9a%2B3b%2Bc=8\"
\n" ); document.write( "THREE \"+c=2+\"\r
\n" ); document.write( "\n" ); document.write( "then you start with ONE and THREE
\n" ); document.write( "\"+a%5E2-b%2Bc=5+\"
\n" ); document.write( "\"+c=2+\" < multiply each side by -1
\n" ); document.write( "and add to get a-b=3\r
\n" ); document.write( "\n" ); document.write( "Im not sure if thats the way to go where you then use equation 3 to eliminate c from equation 2 or if there's another process to get solutions of a, b and c? I'm thankful for any advice on this problem!
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Algebra.Com's Answer #694312 by josgarithmetic(39620)\"\" \"About 
You can put this solution on YOUR website!
First use the point of one of the given roots, (0,2).\r
\n" ); document.write( "\n" ); document.write( "\"y=a%2A0%5E2%2Bb%2A0%2Bc\"
\n" ); document.write( "\"2=0%2B0%2Bc\"
\n" ); document.write( "\"highlight%28c=2%29\"\r
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\n" ); document.write( "\n" ); document.write( "Make two equations with each of the other given points.
\n" ); document.write( "\"ax%5E2%2Bbx=y-c\"
\n" ); document.write( "\"ax%5E2%2Bbx=y-2\"
\n" ); document.write( "-
\n" ); document.write( "\"a%2A%28-1%29%5E2%2Bb%2A%28-1%29=5-2\"
\n" ); document.write( "\"a-b=3\"
\n" ); document.write( "-
\n" ); document.write( "\"a%2A3%5E2%2Bb%2A3=8-2\"
\n" ); document.write( "\"9a%2B3b=6\", simplifiable,
\n" ); document.write( "\"3a%2Bb=2\"
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\n" ); document.write( "Now solve this system: \"system%28a-b=3%2C2a%2Bb=2%29\"
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