document.write( "Question 102791: 24x²-2x=15 solve the equation by factoring and quadratic formula \n" ); document.write( "
Algebra.Com's Answer #74796 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"24x²-2x=15 solve the equation by factoring\"\r
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\n" ); document.write( "\n" ); document.write( "\"24x%5E2-2x=15\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"24x%5E2-2x-15=0\" Subtract 15 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"%286x-5%29%284x%2B3%29=0\" Factor the left side (note: if you need help with factoring, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "Now set each factor equal to zero:\r
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\n" ); document.write( "\n" ); document.write( "\"6x-5=0\" or \"4x%2B3=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=5%2F6\" or \"x=-3%2F4\" Now solve for x in each case\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are \r
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\n" ); document.write( "\n" ); document.write( "\"x=5%2F6\" or \"x=-3%2F4\" \r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph \"y=24x%5E2-2x-15\" we get\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C+24x%5E2-2x-15%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the graph has roots at \"x=5%2F6\" and \"x=-3%2F4\", so this verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "\"4x²-2x=15 solve the equation by the quadratic formula\"\r
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\n" ); document.write( "\n" ); document.write( "\"24x%5E2-2x=15\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"24x%5E2-2x-15=0\" Subtract 15 from both sides\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x:\r
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\n" ); document.write( "\n" ); document.write( "Starting with the general quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"ax%5E2%2Bbx%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"\r
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\n" ); document.write( "\n" ); document.write( "So lets solve \"24%2Ax%5E2-2%2Ax-15=0\" ( notice \"a=24\", \"b=-2\", and \"c=-15\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--2+%2B-+sqrt%28+%28-2%29%5E2-4%2A24%2A-15+%29%29%2F%282%2A24%29\" Plug in a=24, b=-2, and c=-15\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+%28-2%29%5E2-4%2A24%2A-15+%29%29%2F%282%2A24%29\" Negate -2 to get 2\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4-4%2A24%2A-15+%29%29%2F%282%2A24%29\" Square -2 to get 4 (note: remember when you square -2, you must square the negative as well. This is because \"%28-2%29%5E2=-2%2A-2=4\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4%2B1440+%29%29%2F%282%2A24%29\" Multiply \"-4%2A-15%2A24\" to get \"1440\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+1444+%29%29%2F%282%2A24%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+38%29%2F%282%2A24%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+38%29%2F48\" Multiply 2 and 24 to get 48\r
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\n" ); document.write( "\n" ); document.write( "So now the expression breaks down into two parts\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B+38%29%2F48\" or \"x+=+%282+-+38%29%2F48\"\r
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\n" ); document.write( "\n" ); document.write( "Lets look at the first part:\r
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\n" ); document.write( "\n" ); document.write( "\"x=%282+%2B+38%29%2F48\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=40%2F48\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=5%2F6\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So one answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=5%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "Now lets look at the second part:\r
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\n" ); document.write( "\n" ); document.write( "\"x=%282+-+38%29%2F48\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-36%2F48\" Subtract the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=-3%2F4\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So another answer is\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=5%2F6\" or \"x=-3%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"24%2Ax%5E2-2%2Ax-15\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-13%2C+15%2C+-13%2C+15%2C24%2Ax%5E2%2B-2%2Ax%2B-15%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=5%2F6\" and \"x=-3%2F4\". This verifies our answer\r
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