document.write( "Question 194493: find the equation of a quadric function with x- intercepts (2,0) and (-7,0) and y intercept (0,5)\r
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Algebra.Com's Answer #145933 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Since the equation has the x- intercepts (2,0) and (-7,0), this means that the roots are \"x=2\" or \"x=-7\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=2\" or \"x=-7\" Start with the given roots.\r
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\n" ); document.write( "\n" ); document.write( "\"x-2=0\" or \"x%2B7=0\" Get everything to the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"a%28x-2%29%28x%2B7%29=0\" Combine the equations using the zero product property. Also, insert the variable \"a\" (this will be used to make the graph have a y-intercept of (0,5))\r
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\n" ); document.write( "\n" ); document.write( "\"a%28x%5E2%2B5x-14%29=0\" FOIL\r
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\n" ); document.write( "\n" ); document.write( "So the general equation with the x- intercepts (2,0) and (-7,0) is: \"y=a%28x%5E2%2B5x-14%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=a%28x%5E2%2B5x-14%29\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=ax%5E2%2B5ax-14a\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"5=a%2A0%5E2%2B5a%280%29-14a\" Plug in \"x=0\" and \"y=5\" (from the point (0,5))\r
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\n" ); document.write( "\n" ); document.write( "\"5=-14a\" Multiply and simplify\r
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\n" ); document.write( "\n" ); document.write( "\"5%2F%28-14%29=a\" Divide both sides by -14.\r
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\n" ); document.write( "\n" ); document.write( "\"a=-5%2F14\" Reduce and rearrange the equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=ax%5E2%2B5ax-14a\" Go back to the previous equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=-%285%2F14%29x%5E2%2B5%28-5%2F14%29x-14%28-5%2F14%29\" Plug in \"a=-5%2F14\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-%285%2F14%29%2Ax%5E2-%2825%2F14%29x%2B5\" Multiply and simplify\r
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\n" ); document.write( "\n" ); document.write( "So the quadratic equation is \"y=-%285%2F14%29%2Ax%5E2-%2825%2F14%29x%2B5\"\r
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\n" ); document.write( "\n" ); document.write( "Here's a graph to visually confirm the answer:\r
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