document.write( "Question 465444: How do you create a quadratic equation if you only have the solutions? I am really not getting the quadratic equation math at all. Example if I have theses two numbers, 8 and 4/5 as solutions to create a quadratice equation. \n" ); document.write( "
Algebra.Com's Answer #318973 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
A quadratic equation is one in which the
\n" ); document.write( "highest power of \"x\" is \"2\".
\n" ); document.write( "This will automatically happen when you
\n" ); document.write( "multiply something like \"+%28x+%2B+2%29%2A%28x+-7%29+\"
\n" ); document.write( "You get \"+x%5E2+-+5x+-+14+\"
\n" ); document.write( "---------------------
\n" ); document.write( "Now suppose you have 2 solutions to a
\n" ); document.write( "quadratic equation,
\n" ); document.write( "(1) \"+x+=+8+\"
\n" ); document.write( "(2) \"+x+=+4%2F5+\"
\n" ); document.write( "-----------
\n" ); document.write( "Subtract \"8\" from both sides of (1)
\n" ); document.write( "(1) \"+x+-+8+=+0+\"
\n" ); document.write( "Subtract \"+4%2F5\" from both sides of (2)
\n" ); document.write( "(2) \"+x+-+4%2F5+=+0+\"
\n" ); document.write( "----------------
\n" ); document.write( "The key now is that if you multiply (1) and (2),
\n" ); document.write( "you will have \"+0%2A0+=+0\", so
\n" ); document.write( "\"+%28x-8%29%2A%28x-4%2F5%29+=+0+\"
\n" ); document.write( "Now do the multiplication
\n" ); document.write( "\"+x%5E2+-+8x+-+%284%2F5%29%2Ax+%2B+32%2F5+=+0+\"
\n" ); document.write( "Multiply both sides by \"5\"
\n" ); document.write( "\"+5x%5E2+-+40x+-+4x+%2B+32+=+0+\"
\n" ); document.write( "\"+5x%5E2+-+44x+%2B+32+=+0+\" answer
\n" ); document.write( "--------------------
\n" ); document.write( "Now you can check the answer
\n" ); document.write( "Does \"+x+=+4%2F5+\" work?
\n" ); document.write( "\"+5%2A%284%2F5%29%5E2+-+44%2A%284%2F5%29+%2B+32+=+0+\"
\n" ); document.write( "\"+5%2A%2816%2F25%29+-+44%2A%2820%2F25%29+%2B+32+=+0+\"
\n" ); document.write( "Multiply both sides by \"+25+\"
\n" ); document.write( "\"+80+-+880+%2B+800+=+0+\"
\n" ); document.write( "\"+880+-+880+=+0+\"
\n" ); document.write( "\"+0+=+0+\"
\n" ); document.write( "OK
\n" ); document.write( "You can check the other solution
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