document.write( "Question 77691: How do you find equations for polynomials when only given their graphs?? \n" ); document.write( "

Algebra.Com's Answer #55716 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
You can approximate the equation by looking at its roots\r
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\n" ); document.write( "\n" ); document.write( "For instance, this graph\r
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\n" ); document.write( "\n" ); document.write( " $\"+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+%28x%2B5%29%28x-3%29%29+\"$ \r
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\n" ); document.write( "\n" ); document.write( "has roots of x=-5 and x=3. So for any root of x=a, the factor will be \r
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\n" ); document.write( "\n" ); document.write( " $\"x-a=0\"$ . So if we have roots of x=a and x=b, then our factorization is:\r
\n" ); document.write( "\n" ); document.write( " $\"%28x-a%29%28x-b%29=0\"$ \r
\n" ); document.write( "\n" ); document.write( "So this means our factorization is $\"%28x%2B5%29%28x-3%29\"$ since we have roots of x=-5 and x=3\r
\n" ); document.write( "\n" ); document.write( "Now we just foil $\"%28x%2B5%29%28x-3%29\"$ to get $\"x%5E2%2B2x-15\"$ . This doesn't work all the time since we might have a stretch or compression factor. \n" ); document.write( "

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