document.write( "Question 89362: Solve by using the quadratic formula.\r
\n" ); document.write( "\n" ); document.write( " 5x^2 + x = 3
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Algebra.Com's Answer #64932 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"5x%5E2+%2B+x+=+3\"\r
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\n" ); document.write( "\n" ); document.write( "\"5x%5E2+%2B+x+-+3=0\" Subtract 3 from both sides\r
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\n" ); document.write( "\n" ); document.write( "Now 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%2Bx-3=0\" ( notice \"a=5\", \"b=1\", and \"c=-3\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+%281%29%5E2-4%2A5%2A-3+%29%29%2F%282%2A5%29\" Plug in a=5, b=1, and c=-3\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+1-4%2A5%2A-3+%29%29%2F%282%2A5%29\" Square 1 to get 1 \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+1%2B60+%29%29%2F%282%2A5%29\" Multiply \"-4%2A-3%2A5\" to get \"60\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+61+%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+=+%28-1+%2B-+sqrt%2861%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+=+%28-1+%2B-+sqrt%2861%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+=+%28-1+%2B+sqrt%2861%29%29%2F10\" or \"x+=+%28-1+-+sqrt%2861%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=-1%2F10%2Bsqrt%2861%29%2F10\" or \"x=-1%2F10-sqrt%2861%29%2F10\"\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=0.681024967590665\" or \"x=-0.881024967590665\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=0.681024967590665\" or \"x=-0.881024967590665\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"5%2Ax%5E2%2Bx-3\", 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=0.681024967590665\" and \"x=-0.881024967590665\".So this verifies our answer
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