document.write( "Question 187247: If the zeroes of a quadratic function are -4 and 6, and its y-intercept is 12, determine the function in general form without using regression.
\n" ); document.write( "My name is Chantal and I know that -4 and 6 are the roots and -12 is the last part of the equation in general form but I don't know what he means by regression. I'm not sure how to go about doing this equation. If you could help me it would be greatly appreciated. I missed school when we learnt this.This is not from a book.
\n" ); document.write( "Chantal Laroche
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Algebra.Com's Answer #140352 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"If the zeroes of a quadratic function are -4 and 6\" means that the solutions to the equation \"ax%5E2%2Bbx%2Bc=0\" are \"x=-4\" or \"x=6\" (ie if you plug in \"x=-4\" or \"x=6\" into \"ax%5E2%2Bbx%2Bc\", you will get zero)\r
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\n" ); document.write( "\n" ); document.write( "\"x=-4\" or \"x=6\" Start with the given solutions\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B4=0\" or \"x-6=0\" Get the terms to the left side (so the right side is zero)\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B4%29%28x-6%29=0\" Combine the equations using the zero product property\r
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\n" ); document.write( "\n" ); document.write( "Note: the zero product property states that if \"A%2AB=0\" then either \"A=0\" or \"B=0\" (or possibly both)\r
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\n" ); document.write( "\n" ); document.write( "\"a%28x%2B4%29%28x-6%29=0\" Place an additional variable \"a\" onto the front of the equation. Note: this will be needed to satisfy the third condition.\r
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\n" ); document.write( "\n" ); document.write( "\"a%28x%5E2-6x%2B4x-24%29=0\" FOIL\r
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\n" ); document.write( "\n" ); document.write( "\"a%28x%5E2-2x-24%29=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So the equation that has the zeros of -4 and 6 is \"y=a%28x%5E2-2x-24%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now there's an additional condition: The y-intercept is 12\r
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\n" ); document.write( "\n" ); document.write( "This means that when \"x=0\", \"y=12\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=a%28x%5E2-2x-24%29\" Start with the previous equation.\r
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\n" ); document.write( "\n" ); document.write( "\"12=a%280%5E2-2%280%29-24%29\" Plug in \"x=0\" and \"y=12\"\r
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\n" ); document.write( "\n" ); document.write( "\"12=a%280-2%280%29-24%29\" Square 0 to get 0\r
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\n" ); document.write( "\n" ); document.write( "\"12=a%280-0-24%29\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"12=a%28-24%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"12%2F%28-24%29=a\" Divide both sides by -24 to isolate \"a\".\r
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\n" ); document.write( "\n" ); document.write( "\"-1%2F2=a\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So the value of \"a\" is \"a=-1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "This means that the equation then goes from \"y=a%28x%5E2-2x-24%29\" to \"y=%28-1%2F2%29%28x%5E2-2x-24%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now distribute to get: \"y=%28-1%2F2%29%28x%5E2%29-%28-1%2F2%292x-%28-1%2F2%2924\"\r
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\n" ); document.write( "\n" ); document.write( "and multiply: \"y=%28-1%2F2%29x%5E2%2Bx%2B12\"\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the equation with the zeros -4 and 6 with the y-intercept of 12 is:\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F2%29x%5E2%2Bx%2B12\"\r
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\n" ); document.write( "\n" ); document.write( "Here's the graph to visually verify our answer:\r
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\n" ); document.write( "\n" ); document.write( "Graph of \"y=%28-1%2F2%29x%5E2%2Bx%2B12\" with x-intercepts (-4,0) and (6,0) with the y-intercept (0,12)
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