document.write( "Question 91107: Please help me solve this, 5x^2 + 14x = -3 \n" ); document.write( "
Algebra.Com's Answer #66135 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"5x%5E2+%2B+14x+=+-3\"\r
\n" ); document.write( "\n" ); document.write( "\"5x%5E2+%2B+14x+%2B3=0\" Add 3 to 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 \"5%2Ax%5E2%2B14%2Ax%2B3=0\" ( notice \"a=5\", \"b=14\", and \"c=3\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-14+%2B-+sqrt%28+%2814%29%5E2-4%2A5%2A3+%29%29%2F%282%2A5%29\" Plug in a=5, b=14, and c=3\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-14+%2B-+sqrt%28+196-4%2A5%2A3+%29%29%2F%282%2A5%29\" Square 14 to get 196 \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-14+%2B-+sqrt%28+196%2B-60+%29%29%2F%282%2A5%29\" Multiply \"-4%2A3%2A5\" to get \"-60\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-14+%2B-+sqrt%28+136+%29%29%2F%282%2A5%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-14+%2B-+2%2Asqrt%2834%29%29%2F%282%2A5%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+=+%28-14+%2B-+2%2Asqrt%2834%29%29%2F10\" Multiply 2 and 5 to get 10\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+=+%28-14+%2B+2%2Asqrt%2834%29%29%2F10\" or \"x+=+%28-14+-+2%2Asqrt%2834%29%29%2F10\"\r
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\n" ); document.write( "\n" ); document.write( "Now break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"x=-14%2F10%2B2%2Asqrt%2834%29%2F10\" or \"x=-14%2F10-2%2Asqrt%2834%29%2F10\"\r
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\n" ); document.write( "\n" ); document.write( "Simplify\r
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\n" ); document.write( "\n" ); document.write( "\"x=-7+%2F+5%2Bsqrt%2834%29%2F5\" or \"x=-7+%2F+5-sqrt%2834%29%2F5\"\r
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\n" ); document.write( "\n" ); document.write( "So these expressions approximate to\r
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\n" ); document.write( "\n" ); document.write( "\"x=-0.23380962103094\" or \"x=-2.56619037896906\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=-0.23380962103094\" or \"x=-2.56619037896906\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"5%2Ax%5E2%2B14%2Ax%2B3\", we get:\r
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\n" ); document.write( "\n" ); document.write( "when we use the root finder feature on a calculator, we find that \"x=-0.23380962103094\" and \"x=-2.56619037896906\".So this verifies our answer
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